"Huck" couldn't be further from the correct assumption!!
As wisely explained to me after long reasearch by a very smart NSX tech here, (L.B) the problem was caused by sub standard cutting tools at Honda. When the normal amount of cuts were made and the tool was changed it was expected to cut a given number of cases before it wore. Not known to the Honda engineers the tool was softer than standards directed so the few cuts toward the end of the cutting run were not in tollerance and the groove was wider than normal before the tool was exchanged.
The first case cuts of the tool life WERE in tollerance and there's nothing wrong with them but no one knows just when the machine made compensations for the dull tool by serial number, and the groove opened up the tollerance that allows the snap ring to move in the groove and after time and usage can cause it to break.
MANY transmissions have a good life as a normal one but the serial numbers of them aren't known and that's why when these cars were new there was a recall for that reason.
These cars are twenty years old and Honda isn't going to perform a recall from then.
The parts for the fix aren't free but not so expensive that upon the next timing belt / or clutch change it might be smart to do the case update to be sure.
Update kits are avialable from S.o.S. amoung otherplaces.
The Acura M.M. is a great resource for info for s/n location and their s/b describes this problem and repair in length
My car is in snap ring range and going in for a timing belt/water pump change next week. Do you guys think that this would be a good time to be proactive and have the snap ring issue fixed or just wait and hope it doesn't fail?