Regarding the digital audio (rather than MIDI)
approach, I'll try to
space the punchin and punchout points a little farther apart than I
normally would, to give me a greater choice *after* re-recording the
section as to exactly where I want the actual punch to occur. (I hadn't
thought of that, obvious though it may now seem. ;-)
i'm missing something probably, but why would you punch in/out on a daw
when you can just create a new track, play along during the section
you'd like to replace, and then cut/paste edit to replace the other
part?