wow, im not sure what order the posts were actually made in. LOL. BMJ, if you were not completely disengaging the clutch all the way (what happens when the clutch engages right off the floor), i dont see how your clutch would have been adversely affected. you would just have had, perhaps, some rough shifting (depending how close to the floor the POE really was).
it is the other extreme from slipping, so you might be alright.
for the slipping, did you leave some freeplay in the cable? while i know V8 et al, like to dial in preload, having slack in it for now tells you that you are not slipping one bit from preloading the cable - if it slips, it should be all clutch hardware in the bellhousing (not the quadrant, cable, etc).
my ramblings. good luck.