emerge -P shothand for emerge prune is too close to completely different -p switch. If you are checking out what is going to be emerged and accidentally write -UDP instead of -UDp you will get *very* different results. (Yes, I have done it once and I swithced to another window before seeing the countdown) I would suggest to either remove the -P switch completely or rename it to something else. Reproducible: Always Steps to Reproduce:
No. Inattention is no reason for change.
That's a fairly weak argument. There's no reason a typo like this should trash someone's system (which is what typically happens), even if they are distracted at the critical time.
Err.. prune gives you a warning (Unmerging in...), and a delay. If that's not enough indication the user boned up the request to do --pretend, don't know what else to say.
