I read something the other day from Martinez, TB12's mechanics coach. In it he said that TB12's deep ball had been poor until the arrival of Moss.
Anyway, I had a look at http://www.youtube.com/watch?v=R0zmA-M0v4c
And you know what - he's right. Quite a few of the bombs were horrifically underthrown and it was only the genius of 07MOSS that avoided them being INTs or worse.
Nowadays, TB12's deep ball (which is rare) is usually pretty bang on. And he seems to overthrow more than underthrow (e.g. Gronk open down the seam.)