I did not claim that open interest did not matter, just the stated max pain. Also I'm not sure if by deceptive scale you are talking about a chart that I pasted a while ago (because it didn't just compare fridays) but for the purposes of options trading like some do here with fairly high delta, a very small deviance can have a big effect.Also just a "chart with deceptive scale only comparing friday close with official MP" doesn't tell the whole story.
We've seen lots of weeks where MP was weird because of way OTM options, but there was a fairly obvious "realistic" target for the MMs, and it'd frequently close within pennies of it.