if the runners forward motion is stopped at any point the they should whistle it dead and spot the ball there.
oftentimes the runner is stopped cold, and then others start pushing and pile goes forward.
That is part of the problem, on qb sneaks, and with rb runs.
Phil almost always does it to left of center, so who do they have there?
Hurts uses standard method, look for the gap and get low.
However since no whistle is blown if he is stopped, then the whole pile can be pushed forward after being stopped initially.
Hurts is often getting the 1st by himself, but if stopped short, the guys behind can push him forward.
Other teams should be able to do this too, but evidently they ( the coaches ) just are not smart enough to implement it.
It isnt rocket science lol So that is the only answer I see.
Sadly this includes the cowboys lol.