+1Quote from sle:
True, though we are starting to deviate from the whole max pain thing.
I think (never done it) that in some assets if you keep track of all institutional purchases (given that most bookies will give you a spam of all trades they are doing, in some sh*t form like "grnH86/88 cs +paper") you could probably have a heat-map of all MM long/MM short positions. If you know of some strike that MMs are very long, you might want to sell these strikes in hope that their delta hedging would squash the realized vol. Similarly, MM hedging a large short position would amplify the realized vol.
Precisely, hence this is a sporadic, statistically insignificant effect. Having watched god knows how many expiries, I have observed it maybe once or twice (if memory serves) .
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