This is NOT a disconcerting signal. It is what it is: an abrupt / exaggerated movement intended to cause a false start. That's how the announcement would go."Before the ball could be sapped, delay of game, number 55, defense; he made an abrupt movement intended to cause a false start. That's a 5 yard penalty, second down."
There does not need to be any reaction by Team A. If we see such a movement, it is a foul. Period. Don't wait for a reaction.
A Disconcerting Signal is a different foul altogether. And, like the abrupt movement to cause a false start, it does not require a reaction by Team A, either. If we hear signals that we know dang well are intended to cause Team A to false start, that's a foul. Period. Don't wait for a reaction.
Lots of teams are coached to do both, under the guise of either just "making a football related move" (caca), or just making a call for the line to "make a football related move" (more caca).
Example: as the snap is imminent, a D-tackle (or many), in a four point stance within one yard of the NZ, abruptly falls and rolls to one side, and quickly rises back to a four-point stance. More often than not, this causes an O-tackle or O-guard to start too soon. They'll claim that he's just moving into a gap or something. Baloney. Don't buy that bovine scat. This is 9-1-5-a-4, a movement intended to cause a false start (with or without a reaction by Team A). (If this was legal, why do you not see it being done on Saturdays?)
Example: as the snap is imminent, linebacker B55 abruptly and sharply shouts, "MOVE." Maybe some defensive players move, maybe they don't. But, more often than not, this causes an/some o-linemen to start early. Again, they'll claim this is just their normal defensive signal. Baloney. Don't buy that bovine scat. This is 9-1-5-a-5, Disconcerting Signals (with or without a reaction by Team A). (Again, if this was legal, why do you not see it being used on Saturdays?)
And don't fall into the trap of "... but they didn't move!" Doesn't matter. Both are fouls, with or without a reaction by Team A.
We just need to have the cajones to make these calls.
Robert