As far as 'rules of thumb', you're the master. It's uncanny that what you recommend is almost exactly as I see it. That said, even when I know better, I still resort to a half-ass method. The question of 'why' has haunted me for ages. I've spent a good deal of time contemplating how to reconcile impulsiveness with good judgement and common sense.I guess it boils down to the bottom line.
P.S. I was thinking needle file, but I've never seen one with a sharp enough edge. When I finish punching those saddles, I'll send a picture. We'll compare notes. Thanks.