'Back' Option for Some Operations?

I suggested this to David Leon at McNeel. I wonder if it could be feasible or useful to some users to be able to go ‘back’ a step in certain commands. I’m thinking Sweep2 in particular where an incorrect second rail fast forwards straight onto the cross sections, if you’re not chaining edges.
So in the command line there could be the possibility to hit ‘B’:

Might only be a very fine timesaver. Just an early thought rather than always escaping the command (again, depends if it’s a complex selection).