No Longer a Potential Blocker

[Mike L]

The problem with this rule is really quite simple. "Potential Blocker", just what the heck is that? It's not well defined anywhere in the book and we are stuck with only a case book play that presents a blatantly obvious example.
So, barring a clear directive from ones assoc, it's simply up to the covering official to decide when the defense has crossed that line between acceptable and non-acceptable contact. And that's why we get the big bucks. If B is in front of A, he can do just about any legal block. If they are side-by-side, realistically all I've ever seen is some incidental contact, but if B knocks A seriously off his path I probably have a foul. If A gets beyond B, 99.9% of the time B isn't going to be blocking anyway, he's going to be grabbing & holding. If A is clearly not acting like a blocker, for example Ed's buttonhook question, I don't know how you can possibly allow a B to just blast him no matter where he's coming from. Potential blockers rarely just stand there looking back at the QB.