> That's certainly possible - I was never able to lure them away before I accessed the troll guarded area though.

It's possible, but it's hard to do by accident. Basically you have to get beneath them, lure them out of the way, then plot a course for the switch that doesn't lure them back in the way before you get there.

> Although every other time I've worked the blocks, the adventurers moved when the block did...

Sounds like a misreading. Blue parties get crushed by the sliding walls, and red parties simply stop the walls from moving at all. You can't ever push a party out of the way.