(Nothing against you here rja, just throwing in a bit of my view) Three things here: 1) I don't think it was helmet to helmet, the angle isn't the best for determining that, 2) AJ wouldn't have made such a crappy throw, 3) assuming AJ would have, if he's going to run over there and stick his nose in the play, he put himself in harms way, so he'd best be wide awake. You are correct in that I wouldn't have liked it, but I wouldn't be lobbying for relief days later. Thus far, unless it snuck past me, I haven't heard Murray complaining, at least openly. If the qb deosn't want to get hit, go away from the play. If Dial had gone across the field, against the flow of play, to hit Murray, then I'd be for a flag.
This whole protecting the qb and/or supposed defenseless wr's needs work. If these type penalties are going to get called; then the rule also needs to apply on peel back blocks. If this whole thing is about player safety, then defenseless is defenseless... regardless of the position you play.