Beckett lost velocity on his fastball? News to me, because his average fastball velocity last year was 93.5 MPH, down from 94.3 the two previous years, however, over the last two months, his velocity creeped up into an average of 94.1, so i have no clue where you came up with that info, good sir.
As for the Tomase article, it seems like more of a "It's Spring Training so there's nothing to write about". And it is, in fact, Spring Training, which is indicative of nothing.
Anyways, Beckett's stuff is still good, but his stamina seems to be lacking, and until he actually gets shelled in the regular season i won't declare him "one and done", because like everyone else here, i don't know the specifics of his throwing program, and i haven't seen any indication of worry from the team.