In my opinion, yes, we're making a mistake.
I understand why DG and RG want to keep their options open and could draft two different kinds of QB depending on if we take one in the draft (and who that rookie QB turned out to be).
But I also am a great believer in making time your friend and not your enemy. The longer we wait, the more likely the pool of available FA's will dry up so that we have fewer QB's to pick from. All this within the context of wanting to have our QB situations stable before training camp - if not earlier.
I also believe that the fewer problems or questions a front office and QB has to address, the more they can focus on doing what's necessary to get the existing team ready to compete. Wondering who our backup QB will be is just one more distraction.