No. There is no need to allow 3-4 hostile pool owners to block all further development of the system. As a first step the nodes could no longer relay blocks of the hostile pool owners. In the second step it is possible to head for an
user activated soft fork.
You're treading into very dangerous and contentious territory here... Trying to do a soft fork behind the miners' backs is sure to cause an uproar. I mean, if you're worried about a hard fork, this would be hundreds of times worse.
If core goes through with this user-driven soft fork, I think it will be the final end of their credibility, and thus they will be done setting the roadmap for bitcoin. Gavin and Garzik would have to pick up where they left off, and we'd all be registering at a new forum.
If this gets bad enough, at some point Satoshi might even come back and bitch-slap the shit out of you fools...