There is no doubt in myu mind that Vinny was brought in for multiple reasons.
1: Certainly as an experienced backup.
Certainly so.
2: To help Brady, along the sidline, with another pair of Quarterback eyes.
Uh, then WHY does he never sit with or talk to Brady along the sidelines???? There not only is no evidence for this opinion, but the evidence directly contradicts the baseless opinion.
3: To offer input into the playcalling. Not necessarily to call the plays, but to offer input if he sees something or thinks that something might work in a given situation.
Then why does he not talk with Josh, BB or whomever during the game? Wait, I get it! He uses mental telepathy! Hey, it's a theory or opinion.
Personally, I believe that the latter was the main reason. I believe that Belichick respects Vinny's experience and his knowledge of offensive, NFL football and that was the main reason he is now on our sideline....
Belichick, again only my opinion, is not tickled pink with the boy Offensive coordinator who is being skunked and out guessed and out coached by most of the DC's on the other side of the field on game days.
Opinion. May be true but there's little evidence to support it.