I'm a Forever GM.  When I was teaching my most recent long-term group to play a couple of years ago, I had one of them run the Beginner Box, and I played a pure support character - a tiny, delicate witch who cast buffs and heals.  A joke character!  An awakened opossum with an opossum as their familiar.

In the final fight against the green dragon, one of my players pointed out that they'd always thought of me as a very tactical player, but they couldn't understand why I went into melee with gouging claw toward the end of the fight, after the fighter had gone down and only the rogue was still up.  

I explained: I had spent every spell slot, every focus point.  All my utility was already on the field, the rogue had Runic Weapon and Life Boost on her, and I knew all I could do was enable her to win the fight.  I only had one resource left to spend: my hit points.  I did it the most efficient way I knew how, casting my highest-damage option from a flanking position, granting a +2 to hit and +1d6 damage and my hit point pool as temporary hit points for her.  And it worked!  I tanked!  For...one round.  But that one round was all we needed to survive that terrifying fight at the end of the Beginner Box against a dragon.

The "ranged attackers only matter for the first couple of turns" claim was always goofy to me. To start, less than half of monsters have reactive strike, so most of the time, you can just stride away. I played in the party where a rogue and  swashbuckler wwre the closest thing we had to a "tank", and the entire party just adopted skirmishing tactics where we did hit and run attacks.

Everyone could heal, between a swashbuckler with Blessed One, an alchemist, a battle mystery oracle, an alchemical science investigator, and a rogue willing to carry elixirs. Our main MO was the alchemist (me) harrassed enemies that were hiding in cover  with bombs; between blight bombs, acid flasks, alchemist fire, and the free alchemist bombs, I was able to stack up enough persistent damage that it made a prolonged conflict extremely unfavorable for the enemies, so they usually sent people out to attack me. The swashbuckler would run in to intercept as I retreated, and the rogue flanked while the investigator fired with a gun. The oracle rotated between melee, blasting, and supporting as needed, and after the initial salvo to flush enemies out of cover, I also rotated to whatever role needed filling. Because we wove in and out of combat, and we could all survive and be helpful in any position, it was extremely difficult for enemies to put us into a position that would stall out our momentum, and it was really easy for us to exploit the swashbuckler's bleeding finisher and my bombs (I also used sticky bombs and gave the investigator exsanguinating ammo) to keep chipping away if we needed to surrender some tempo to heal up

Switch hitting martials are my favourite characters to play, tactical flexibility at its finest.

One of the things I learned about in the late 90s in MUDs is the concept of a "butt-tank"--necessary because of how aggro worked. Sometimes the first person in the room was targeted, sometimes the last.

Strangely applicable to tactical combat outside of MUDs, for the reasons you mentioned: you're not always in the perfect position when the bad guys show up. So for this reason, when I play a "frontline" off-tank, their primary responsibility is having the flexibility to apply damage/effects where they're needed. Which frequently means medium (or lighter) armor combined with the fleet feat, the ability to switch to ranged fighting if melee and vice versa, and the ability to control things that are hitting where the primary tank isn't. Sometimes the only thing a skirmisher needs to do is get into a flanking position or eat an attack or two, and everything after that is just icing on the cake.

I've been in a position of circle-kiting after the primary tank went down, and it (eventually) paid out. You only need about 10-20 feet of lead out if you have any kind of action denial built into your skirmisher.

I couldn’t believe the preview.
Just ~20 hours ago we have had a fight with this exact creature, in the exact same formation as depicted:
A witch in the back, a commander in the middle, a barbarian in the front. The formation actually took us a few hours of discussion before the game as we were discussing who is going to hold the line, by what means, and how to rotate the frontliner in case of bad rolls and huge damage taken.
Couldn’t have had a better timing with this.

I love all Mathfinder videos!

I played a psychic assassin as a guest character in our kingmaker at lvl 12, as I wanted a short break from my current character without killing her off and a fitting opportunity arrived. I built him with unbound step as my concious mind, picking up imaginary weapon via parallel breakthrough, and he was a beast! He was a switch hitter with a mix of control and blasting who set up an advantageous battle state before diving in and dealing massive damage with unleashed imaginary weapons against foes that were usually both frightened (from dark persona's presence) and off-guard.
Come to think of it, the other two characters I played during that campaign were also switch hitters. One was a thaumaturge/alchemist jack off all trades who threw bombs, healed, casted spells, and knew every weakness and how to exploit it. And the other was a kobold rogue trapmaker who kited and/or pushed enemies into her traps.

I definitely encourage people to break out of the "backline who only does x, frontline who only does y" mentality, because the game gets a lot more fun with whackier builds. You can even build for a slightly gimmicky fighting style and make it work as long as you build in things to do when it doesn't work

I'm having tons of fun playing an Oscillating Wave Psychic/Medic as a kind of bait-and-switch offtank, having what basically is a ranged Vampiric Touch as a focus spell from level 1 is super cute. Grabbing armor proficiency at 3 and keeping Shield on Recast, I can usually take several hits on contact, top myself up with an amped Frostbite and a battle heal, and then re-assess. If I don't risk getting one-shot, I can then proceed to keep taunting the enemy to break through 2 more refreshes of Calculate Threats-protected Frostbite temp HP, and if I do, the tank is usually nearby to take the heat off me while I kite back and get to blasting.

Thanks for making/sharing.

Ah, switch hitting. It's a favorite of mine, because it's a pain to fight against. You chase them, they just run away. You make distance, they close in and punch you in the face. Grabbing them just makes them start punching you too. It's wonderful. I realized a while back that one of the reasons switch hitting feels so great is that a lot of the time, you just don't have to give a shit. You just do your thing and nothing really gets in the way of that. You're whatever's needed at the moment.

This is why Dastardly Dash is the best feat in the game. It lets you close in, it lets you dip out, what more could you need? It gives you literally everything necessary to be a good switch hitter. And as a plus, it also lets you be a kiting piece of shit, compressing one action for three, forcing the enemy to spend two whole actions to follow you if you got a successful Trip. It's frankly ridiculous, and even Daredevil doesn't really have anything that could directly compete with this one, single action. And the best part is, you don't even compromise yourself! If the Trip succeeded, they're off-guard. Which means a thrown weapon's exactly as effective as it always could be in melee. And then you have an action left over for whatever else you want to do. Parry, Battle Med, Aid, item, or heck, Stride to make even more distance (which is just disrespectful if I'm being honest)

I've done some opportunistic frontlining as a war mage with SF2 gear (mainly a d6 agile revolver). I cast Hop Skip Jump and made a bespelled strike (which missed), and I then teleported 10 ft away from an enemy our warpriest was tussling. Then I Echo Jumped out and made another bespelled strike which hit this time (yay). Because the enemy failed his reflex, I got to force move him out 10 ft, which combined with the rest of the enemy getting bodied by the party, led to him fleeing instead of Dominating us.

This convo reminds me of a few weeks ago during a Kingmaker session in my first pathfinder game (I'm a large size Mystic). At the last fight with assassins in a noble manor (an extreme one people would likely be familiar with lol, it's deadly at lvl1), my large but squishy caster stood beside the two martials at the doors to partially block the entrance after applying runic weapon on the rogue.

My positioning at the start prevented the assassins from getting around the group to start flanking, and I tanked a hit from the boss (although barely lol) which helped the martials not get knocked down early. Eventually as the battle continued I was able to use my closer position (I stepped back after the hit, but stayed close with Malediction up for a debuff to enemy AC) to setup flanking for both the fighter and rogue--allowing them to crit on the boss multiple times and bring her down within a couple turns.

The DM said that was one of the cleanest versions of that fight he has seen. Now obviously there was luck with us for rolls, and I got an important heal from our sorcerer to keep me up along with the martials doing their things, but being where I was--even as a physically weaker caster--made an important difference in the math at a couple key points.

Love your videos Mathfinder! I've found them really useful as I start playing the game and try to figure out things <3

I've played basically that exact Druid you mentioned, with the Mauler archetype. I wasn't ever the main melee bruiser, the Fighter was, and I was the team's dedicated healer on top of being a full spellcaster so I always had something do to, but sometimes that 'something' was rushing in to help the Rogue flank, sometimes it was making sure the boss has a third target to aim for if I was at full HP and the melees weren't, and sometimes it was just smashing things that looked low with a big two-hander, one that does only a smidge less damage as the Fighter's regular strikes, mind you.

I was a Waves Druid, at that, so I could dip in and out of melee range even through difficult terrain with a single action and a focus point. After I did my bonking, if the heat came down I would just Rising Surf away and shoot behind me with a max-level spell slot. I'm not even risking a Reactive Strike if I hit whatever monster came by with a Trip or Shove before doing that, which is not out of the question since I had a decent Athletics and don't need to keep both hands on the weapon if I'm leaving melee anyways, though that admittedly does limit the spell options on the same turn

I love some of the examples of reasons why you might need to change positioning here

I like all my characters having a bit of versatility when I make them. Especially being able to move and get a good strike in where needed. I think the only time id ever consider a static front and back like is if youre surrounded and you want a defensive ring around your squishies, but even then you need to swap your walls out for a breather when needed

My Civic Wizards has stepped up to provide flanking, and maybe slap out a melee Ignition multiple times. But definitely not all the time. The only HP that matters is the last one!

What a great topic for my first early access video. Currently playing a Guardian and a melee Animist in my two campaigns.

These were a lot of really good thoughts and insights thatll help me in my upcoming game

Amazing! I am playing an investigator that is not melee, not ranged, but a secret third thing (Bon Mot and maneuvers, also free hand shenanigans like doors) and this is really helpful for introducing and summarizing ideas I have been having to optimize strategies with our Rogue and Guardian (gang up pair)

Great video! I played an untamed instinct druid and took advantage of untamed shift to occasionally switch hit for a claw attack. Super fun character. I also played an Avenger Rogue switch hitter with a star knife that had the returning rune. She was really fun for going back and forth in and out of melee.