Random anecdote - I recently bought FocusTune software, I am an inveterate focus tuner on all my cameras. In the software instructions, Michael Tapes advocates the occasional LiveView shot as a comparator and/or setup aid. The FT software is interesting in that it calls for one to shoot 4 shots at each AF fine tune setting to ultimately judge the AF fine tune value producing the best sharpness pattern (after outliers are all thrown out). Interesting technique and probably a good thing to use 4 shots since inconsistent PDAF is kind of a known phenomenon these days/comes with the PDAF territory especially with fast lenses wide open and high res sensors.
I was SHOCKED to see that the LV focus was not consistent from shot to shot. This surprised me since the LV focus is the purported gold standard from which one is to judge whether one has the dreaded "left AF point problem". Be careful out there with your testing!
Anyhow my October vintage camera appears to be fine, so I am not worried about my camera and my real world results are good.