I think the point is this.........if TT plays lights out this year and can prove that he is our future, then it's a major bonus for the team going forward, as the QB questions will be put to rest.
However, if TT struggles during the season, then it's comforting for the FO office to know that they will have 2 first round picks for 2018 and can be a major player for a QB, if needed.
You'd rather have options, than none.
In years past, the Bills have handcuffed themselves in the drafts and through FA..........next year affords the organization some breathing room.