You have to question the teams that think a number of mediocre QBs equate to one decent one. I think the Jets are doing something like that now (Pennington - good but not great, Ramsey - again, not bad - though we probably haven't seen everything he has to give, and then say for the sake of argument they draft Cutler who, whilst having long term prospects is essentially a rookie), the Dolphins did it with Feeley and Frerotte, and arguably the Bills are about to do it again (even if they traded to get some kind of stud, they're still a year or two away). What happens is you pay 2 or 3 guys average QB money, meaning essentially you pay a stud, and only get a third of its value.
I suppose what I am saying is the more economical strategy is to isolate your number 1, try and find a passable #2 (though I suspect this strategy is contingent on a team with winners at positions other than just QB, especially on defense) at a lesser salary and then a project #3. I think that maximises value from the position much more than paying 3 guys and hoping one comes through. But then, you need a decent FO to pick that number one guy accurately in the first place. Just some thoughts.