As to this OP - I see it different than some.
From what I can gather, this happened in TC or very early in the season. Gronk was playing poorly or at least below his standards (which makes me believe it was during TC). And Bill does what he does. He doesn't call out some camp fodder, he calls out the guys who should know better. If you are familiar with Bill's dry humor and digs, it seems perfectly in character to call out Gronk and bait him with the Guerrero new age method. I bet it was half tongue in cheek and half what he was feeling at the time.
Who knew that Gronk was such a wooosss. He's been coddled by this team more than anyone over the year, certainly much more than Brady ever was, and if these reports are true, I am really disappointed with him. I expect a lot more from him.
Again, if true, given him some more money in incentives.....or not. Ride him hard this season, which I hope its his best, then, quite frankly, allow him to "be free". Better a year too early than a year too late, or whatev.er cliche you want to pull out. But the fact is, that (again if true), I wouldn't trust Gronk enough now to pay him what he is going to want to keep playing.
I really think this is less about Guerrero than most of the media and fans think. I think it is more about Bill calling out one of his stars and happened to use Guerrero as a needle, and the star didn't take it well. Well too bad.
I don't credit Bill with any blame in this. He was being true to his nature and his well proven philosophy of team building. Where I might offer some constructive criticism, if he is listening, is that I would have had a sit down with Gronk this off season to attempt to iron it out, man to man. OR at least tell him to toughen the f*ck up and stop being such a millennial.