Currently, there is no indication that I pressed a letter to choose an
option after asked some question by darcs. If my computer is slow, it
can result in my being unsure whether I have pressed one, and pressing
it again. And that might possibly result in e.g. two hunks being
accepted, when I wanted only the first. Echoing the letter would make
it possible for me to see whether the key got there.

Keep up good work.