All righty, I mostly stepped away from the keyboard for a couple of days and I'm less frustrated and angry.
So first, I want to apologize to Luke for calling his CODEHASHCHECK code "a joke." I was frustrated that after weeks of discussion and gathering consensus around /P2SH/ he and piuk (and a couple others) decide it would be a good idea to propose slightly-different-but-not-obviously-better alternatives.
I still think Luke went about this the wrong way; for example, I think I would have been happy to accept a patch that made supporting /P2SH/ optional if he had presented it rationally instead of posting "ALERT! GAVIN IS HIJACKING BITCOIN! ACTION NEEDED!" I'd still be happy to accept a patch turning on/off the "put /P2SH/ in the coinbase" (assuming the general consensus is that is a good idea), but that's a discussion that should happen in the Dev/Tech forum.
In fact, most of the discussion in this thread on the merits of various proposals belongs in the Dev/Tech forum, and most of the concerns expressed here in this thread have already been discussed over the last several months.