Someone who signs himself "JonesR" writes to ask…
Do you know any history of the collaboration of Parker and Hart (I'm checking the obit as I write this). Because I was always curious as to, well, at least, who wrote and who drew, and if they may have both at times done either.
I figured that Hart did the character designs, then pretty much let Parker run with it. Parker may have had a history of providing gags to B.C. Or Hart may have given gags to Wizard of Id in the same sense that the Mort Walker crew might work out the gags on three different strips running, or the way some of the Simon/Kirby work seemed to leave the casual reader with a sense of not really being quite sure who may have been doing what.
My understanding is that Parker did no writing. Hart had a team of helpers — friends, assistants, gag writers, whatever you want to call them. Hart acted as Head Writer for a squadron that wrote both strips. The gags for Wizard of Id were sent to Parker and it was his job to get them drawn, which he did with increasing help over the years. The gags for B.C. were drawn by Hart with a little assistance.
Initially, the characters for Wizard were designed by Hart, Parker and a few others all sitting around a hotel room with ample drawing paper and liquor. Thereafter, sketches were exchanged by mail, fax or occasionally in person.
As anyone who's worked in a collaborative situation will tell you, there are times when contributions blur and even the guys who did the work aren't sure who contributed what. In gag-writing, it's not at all uncommon for Mutt to come up with a joke and Jeff to rephrase it and both guys to think they wrote it. I'll bet a lot of the jokes in both strips fall into that category.
The Hogan's Alley site has up a good interview with Hart in which he talks about his work, including much about the team that aided him with the writing. This chat is about thirteen years old and my understanding is that some of the aides changed in that time, plus Parker handed off more and more of the drawing duties on The Wizard of Id to others. But the modus operandi remained pretty much the same.