re: Did anybody see how open Meachem was on the henderson 79 yrd TD

It's most likely what other people said, but it's hard to say with angle.

Ok, I watched the replay with the camera behind Brees. It does look like the safety starts to creep over to Meachem side but quickly comes back to the middle of the field once he sees Devery streaking down the field.

The thing about that play is that it's play action and Drew doesn't have as much time to survey the field. The play is designed to go to Devery. Drew has to fake the hand off, look of the Devery for a second and then throw it to the spot. Drew said after the game that he just had to trust Devery to get there.