I read that in real life David Groh and Valerie Harper were good friends, and remained such until he died. She said they kept in touch. If I had been a writer for the scripts, I'd have kept the duo happily married, but having some 'adventures' together. The episode Bump in the Night consisted of a sort of adventure for Rhoda. I'd have had Rhoda work with Jack alot sooner.
I remember reading in Valerie's bio that phasing Joe out was painful. They knew it was coming, and they did it rather slowly over many episodes and that David's last episode was a sad week on their set. She also mentioned that he had just bought a house in Los Angeles not long before they decided to have Rhoda and Joe divorce...luckily he kept working throughout the rest of his life.