Yeah well, what can I say ... totally resonates, except that for me, the "getting in the zone" part is most definitely not two hours, rather tends to stretch to 4am if not worse.

And the "write down everything and go home" is:

a) extremely frustrating

b) cant get anywhere near to dumping the amount of context that's flying in my head while I code/build. Most of it evaporates if I don't get to the end.

So ... agree with the problem, really not sure I agree with the solution.