I've had a thought tumbling around my head the past couple weeks, and it goes something like this:Most every Eagles fan, even the ones who've been on the Vick bandwagon pretty much from the first time he exploded on the field this season, still aren't really in love with the idea of giving Kevin Kolb away. Maybe he's not Mike Vick, sure, but he's shown an awful lot of ability when he's been out there. And while he's never going to be the running threat Vick is, arm strength can be built (ask Tom Brady) and there's a decent chance he's already the best red zone QB on the team.On the other hand, what does it say when every quarterback the Eagles throw out there plays pretty much the same way? Toss out Jeff Garcia if you want -- since he had his formative years elsewhere -- but at what point are McNabb, Vick, Feeley (the one who came back) and Kolb no longer a coincidence? Are we really tossing away that much potential long-term value by trading Kolb, if all we have to do is draft some other QB this year, put him through the Reid/Marty quarterback academy, and then watch him take over the team in 2015?Consider this comment on the Domo piece my brother passed my way this morning:And for those still burying McNabb, and taking shots, at this point last year (before losing to Dallas), the Eagles were 11-4, and had actually scored three more points (429-426.) And remember, that Dallas was much stronger last year than this year.(The whole comment's pretty good, actually. Scroll down to MG44 to read it.)There are some complications, of course. You need Vick to stay healthy while the new guy gets up to speed, but there's no guarantee Kolb would be any luckier in avoiding injury if you let Vick walk. Even more importantly, the guy you want to draft has to a) exist and b) be available around a spot you're comfortable picking him. How many years can we really sit around waiting for that guy to fall into our laps?Ok, so that's where I was a few days ago. But now consider this: Could the same analysis be applied to Mike Vick?Is Vick really that great a quarterback now -- the rebuilding project is complete and he's going to be great everywhere -- or is he "just" pretty darn good but benefiting from playing in the same system the other guys did?If every QB gives us pretty much the same performance -- just shaped in different ways -- is it worth breaking the bank on Vick when you can keep the younger, cheaper guy around longer and then spend that money improving the many, many ... many areas of this team that need help?If Reid's track record with QBs is so good -- and now that he and Marty have an even better sense of what Kolb needs to work on this summer -- is there any real reason to suspect our offense would be that much worse next year if we let Vick go somewhere else (really, really far away, like Tokyo)?I know it's hard to have a conversation like this without falling back on things like, "Well, this one's kind of short, but he's really fast, and that one can't handle pressure, but he's incredibly sharp in the red zone, and DeSean needs deep balls, etc., etc." But if we zoom out on that discussion for a minute, allowing those distinctions to blur, as long as Reid (and possibly Marty) are crafting the gameplans to maximize each guy's strength and minimize his weaknesses, and as long as we have a years-long track record of at least similar levels of success for every guy other than the one in the Season That Shall Not Be Discussed, does it really matter?Can't we just hold the QB position constant and then figure out how to maximize all the pieces around it?Hmmmm ...