I understand your argument (not fact because the rules do not specifically cover a lineman going in motion behind the LOS and not becoming set again before the snap). In NCAA games, 8 officials might get this right based on your interpretation. In a five man or even 7 man crew at a Texas HS game, I doubt it. Who is going to throw the flag on this? What about the p[layer originally covered? If he catches a pass do you think that will be flagged?
Some of the best officials around have been debating this and I think my solution is the best alternative. However, in a real life situation, the chances of my solution happening are slim. The wing on the side that the player starts on will hopefully have a flag for not resetting as a back, assuming that he follows him across the field to ensure that he doesn't reset as a WR on the line. He also needs to check the number of the player that was originally covered up and note that if it is a pass play he doesn't go downfield. If he does, then he throws his hat and pray there are no other fouls in his area of attention. If the covered player then catches a pass, he throws his face covering (he wanted to get rid of this the whole game anyway).
Then the hard part begins when he, the U and other wing come in to tell you what they have. Good luck with that.
There are really only two things that matter here.
1) Throw a flag for some procedural foul at the snap, doesn't really matter which one or if more than one - they are all five yards from the previous spot, so only one will be enforced, if at all.
2) The originally covered receiver might still be ineligible (rule 7-3-3-c is a bit unclear, I'd actually say that it means whoever is the outermost lineman at the snap, so the now uncovered receiver is eligible - but again, the sensible ruling would be that the covered player stays ineligible until the covering player stops and establishes himself as a back), but that was noted by the wing(s) anyway, right? Just remember that if you see a lineman moving, don't rethink eligibility until he stops.
Yes, this is harder to get (exactly) right if you have only a 4/5 man crew, but by no means impossible. And if you do have the very worst case with the lineman-in-motion going into a pass route and contacting a team B player / being contacted when catching a pass, yeah, it is tough for the crew to get the OPI/DPI sorted out - but huddling and giving the relevant info should help.
"Hey guys, I have a flag for a lineman in motion at the snap, A88."
"Umm, I have a flag on B99 contacting A88 just before the pass got there."
"OK, we'll wave off the DPI [and the ILF] and enforce the ILM. Everybody happy with that?"
How would this be any more difficult than sorting out a down with a "normal" ILM, interception, DEH during the return, and a DB PF? You do have multiple fouls with multiple potential enforcement spots, but just go slow step by step.
