You speak of the evaluation of Tate as if it happens in a vaccuum or is an isolated phenomenon, and it is not. There are many factors involved- the evaluation is interdependent on the other WRs on the roster, the draftees, and the UDFA's.
The time when he will be evaluated again is this summer's OTA, and at training camp. Whoever ends up on the roster is whoever proves themselves the most, whether it be a draft pick, a 2nd year player, or (God Forbid) a 35 year old FA signing.
BB is an EOE when it comes to this evaluation period, he doesn't care what your pedigree is. It is his proclaimed view that everyone starts from the bottom for the new season (although I suspect that even if Welker or Branch stunk it up in camp, they will still end up on the roster).