What about factory manual-trans setups with the MDS already deleted? They have non-MDS lifters... and wouldn't an oil volume issue (if the pump is too small) show up as lower-than-normal pressure at lower RPMs?
i think its accelerated wear at idle. add on vescocity breakdown from the very very light weight oil used and extended life cycles people puy it through isnt helping. lots of 5k and even 10k oil chage intervels being ignored. leads to premature failures.
