I agree, and thought of this possibility when I said "kind of" impossible -- The problem is, if you want to do truly deep thinking on some subject, or get into

I agree, and thought of this possibility when I said "kind of" impossible -- The problem is, if you want to do truly deep thinking on some subject, or get into the meat of a non-trivial problem, the time that you will take to catch back up on where you were will be a limiting factor (and one I think will be too limiting to make substantial progress). The more complex the task is, the more state you'll have to dump (especially if your 30 mins was up and you did not finish a concrete step, but were rather part-way through some sub-step), and over time, that will cut into work/think time. Also, I think your example actually supports my suggestion -- by dumping state and remembering "subtasks", you're breaking up the work into small pieces, right?