There are always more smart people outside your company than within it.
Not all smart people work at Sun Microsystems.
You can drive a car by looking in the rear view mirror as long as nothing is ahead of you. Not enough software professionals are engaged in forward thinking.
That lack of programmability is probably what ultimately will doom vi. It can't extend its domain.
I think multiple levels of undo would be wonderful, too.
Sometimes the easiest way to get something done is to be a little naive about it.