According to your post you claim to know "how it works." Well, despite your belief to the contrary, no institutional client is going to call up a MM and try to jam through a 1.3mm share trade at the close for the simple reason that they know they wouldn't get very good execution. No, in reality, the MM would be given an order so the seller could get the best execution/price. Furthermore, even if someone was stupid enough to do what you are suggesting the MM would have immediately hedged their position with options...which didn't happen yesterday.
Do you understand this? I hope this wasn't too much for you, but, this is how it works.....
