It's a product of other teams trying to outsmart Belichick.
They put themselves in a pretzel.
Only time I've seen it work is when Miami busted out the Wildcat on us. Typically the way to beat the Pats is to get constant pressure up the middle and win the turnover battle because most of the time Belichick won't be out-schemed.
The strategy to beat the Pats has always been pressure on Brady. Easier said than done though.