Questions on the line of scrimmage and lining up

[snrmike]

Unless the backs made a motion that looked like they started the play, the motion is legal as long as they ALL stand still for one second before the snap.

You're kind of at the mercy of the officials on this one though. If they fool one of the officials, that person will be throwing a flag for false start.

The only players required to stay set until the snap are players actually on the line of scrimmage.