Ernie,
I do think a lighter car will break fewer parts than a car with the same HP and an extra 1000 pounds
Factory curb weight on a 76 vette is 3530 and I think a set of slicks on that stock 76 would trash 1 part after the other and I could send of list of the order I broke them in
I think instant HP will kind of jump over the OPPS factor but moving a light car is easier on parts. The 1967 with the 435 horse 427 vette did break a few parts as did the Big Block Shelby Cobras that were doing battle back then but still pretty reliable.