I actually discovered the point trick yesterday. By accident.
I was trying to clean up a point at the end of a long narrow curve, and
started the file at an angle to establish the 'target' line. then the phone
rang. while I was dealing with the call, I noticed that the corner
looked...perfect... Once I was off the phone, I looked a bit closer, and
(you;re right) even though the actual cut only went a little bit into the
surface, it LOOKED like it was all the way through.

A bit more playing, and (depending on grain direction) I can get the same
effect with an X-acto knife or sharp chisel....

thanks!
-James