What is the fastest way to cut a thru hole in a sheet of material where the cutter simply follows the toolpath,stops @ a point, travels down (z-) another .002", again cuts that same toolpath, stops, again feeds down another couple of thousandths, travels the toolpath, etc,etc, finally stoping @ a preset Z- point?

You can do it like this :-

O0001 (MAIN PROGRAM)
G21 G40 G00 G17  (Standard setuplines)

G54 G00 G90 G43 X20. Y0 Z25. H1 M6 (move to start position)
S500 M3 (start spindle)
Z1. M8 (Turn on coolant)
G01 Z0 F50.(feed to top face of work)
M98 P0002 L10 (Divide depth of material by depth of 1 cut to get L figure)
G00 Z25.(Rapid clear)
M30

O0002 (SUB PROGRAM)
G91 (Change to incremental)
G03 I-20. Z-.25 F150. (mill circle and move down)
G90 (Change to absolute)
M99

I have no idea what size you are cutting but this should give you an idea as to how to do it.

Graham.

Use the multi-pass wizard in Mach3.