True, and me neither. Just pointing out that it CAN be declined. Not that we'll see it often though.

True... "Illegal Motion" is a technical term with a definition. As is "Illegal Shift". This play is only one of those two things.

I've seen a lot of teams where that would kill their entire shift & motion strategy, and cause them to lose some of the edge they have from knowing the snap count. I'll explain one common strategy like that:

There are teams that may line up as team A for scrimmage with one or both halfbacks in either the usual halfback or wingback positions. They commonly start a wingback in motion toward the halfback position and then snap & toss the ball to him. Team B seeing this may try to time their defensive charge by inferring the ball is to be snapped when the halfback is at that place in the motion. To keep them from being able to rely on that inference, team A may have the wingback stop at the halfback position, and continue their snap count. But then team B can infer that the ball will be snapped when the other halfback moves similarly. To keep team B from relying on that inference, team A starts the first wingback in motion and, before completing that shift, has the other wingback also begin such a shift. The idea is to take away the possible keys to team B as to both the direction of the play and the timing of the snap, by having 0, 1, or 2 players in the backfield moving pre-snap.

If you say this is simulating action at the snap, you may be correct, but if this is the type of simulating of action at the snap that the rules are designed to preclude, then in effect you're saying the rules forbid team A from having any advantage from knowing -- and hence from having -- the snap count. You might as well say team A has to announce to team B when they're snapping the ball.

No, it's both. Do they not have more than one player in motion at the snap? So it violates the 1st term of 7-2-7. Do they not have a shift that has not ended at the snap? So it violates 7-2-8 also.

Rule book. Clinic. On field Training.

It's interesting, judging by the sample here, that most officials would signal illegal shift for a violation of both Fed 7-2-7 & 7-2-8. It used to be the other way around, an illegal shift call being pretty rare. (Of course there are violations of 7-2-8 that are not violations of 7-2-7.) The rules didn't change, but apparently officials' fashion did.

I concur.

To keep team B from relying on that inference, team A starts the first wingback in motion and, before completing that shift, has the other wingback also begin such a shift. The idea is to take away the possible keys to team B as to both the direction of the play and the timing of the snap, by having 0, 1, or 2 players in the backfield moving pre-snap.

We had a pretty good program here do that a few weeks ago. Must've been a new wrinkle for them because 2 times they tried it out of 3, they were flagged for not resetting for a full second after both were in motion at the same time.

Kill it..
 

Someone else wrote "I always say, when in doubt between shift/motion and false start: kill it as a philosophy. " I have the same philosophy, it is movement on the line before the snap so it should be treated as a dead ball foul as a matter of player safety. JMHO

We are getting way off the beaten path. THIS (the OP) is an illegal shift. Nothing about it simulates action at the snap. There should not be any "when in doubt" as there is no doubt.

That does happen. Sometimes with all the shifting, which sometimes extends beyond what I wrote above and has one or both of the HBs shift back to WB position, they don't leave themselves much time to snap the ball!