To, the flatten cam lobes on the sbc's (especially 305's) helped accelerated those arguments, along with some poor ole' engine builders that hadn't a clue and lost a few rebuilt motors due to cam failure..….
Oil companies certainly didn't make it a front page announcement when they pulled the zinc from around 1200 ppm to about 600 ppm to stop plugg'n up catalytics . Stiff valve springs on a new engine just were killed by it.
