the balk...

[Gee]

The call boils down to umpire judgment and different umpires judge it differently. There is no need to turn your shoulder to see first, just open up your stance a tad.

OBR is more specific as it includes the word 'throw' even though a simple turn under MLB interps is not allowed and could be construed as a feint. I only do OBR and allow a slow turn but not a fast one that drives the runner back.

Again, it depends on the umpire.