Mecanim, looks great in inspector, jitters every loop in game.

I can't get my run animation to look right in the game. In the inspector, both importing the animations, and setting them up within a blend tree, they look great. They loop perfectly. But when I run the game, the loop is not smooth. It's like a chunk of the animation was deleted. Like every time the right foot reaches the ground, it immediately switches to the left foot.

Any ideas? Why would it look perfect in the inspector, but jerky in-game?

well, it fixed itself.... I have no idea how, but it stopped. I think it was the transition conditions.