Of course it would be nice if you could negotiate in things like the Prisoner's dilemma - that's pretty much why you can't. If you could find a common-ish real life analogue of the situation you're thinking about, though, I'd probably give a far less snippy answer :P

As for regretting your choice when the stakes are huge - I think "just dealing with it" is an interesting skill that us humans have, But more seriously, if ALL mistakes are scaled up it shouldn't make any difference to the best option, nor should it make you feel more guilty if you do your best and fail.