I don't think you're totally off base. For the record, I've historically been a "don't trade up" guy. I don't feel like doing any research into finding success stories, but I think generally my point about the narrative around 2nd round QB's being bad could reasonably be applied here.
Another problem with these debates: what is considered successful? I agree, Goff could still flame out. I think a reasonable fan would say Wentz is the real deal, but you can disagree. Let's list some "franchise QB's" Eli Manning, Matt Ryan, Marcus Mariota, Matt Stafford...and let's say Derek Carr for fun. Which of those guys would have been worth trading up for? Eli had some real crappy years, then won 2 super bowl while on a good team. Are you ok with his down years? Mariota started pretty hot then came to earth this year. Would he have been worth trading up for?
I agree with the general approach of looking at costs to trade up and how that worked out from a perspective of teams not being able to fill holes due to not having those draft picks. That has to be considered. I don't agree that a QB suddenly is destined to suck if a team trades up for him. As further noted above, sometimes even good QB's have down years, so it's tough to even definitively state what they were worth to give up. The bottom line is, being a QB in the NFL is really hard, so in order to even have a chance at a good one, you typically need to pay a high price in the form of a high 1st round pick. I think the anti-trade up crowd is saying it's not worth paying an even higher premium to play that game. I guess the philosophical debate then becomes, would you rather put all your chips in for a 10% chance at a home run (franchise QB), or put fewer chips in for a 65% chance at a single or double (really good guard or ILB let's say). Yes, QB's have a lower success rate as compared to their 1st round counterparts, whether a team trades up for them or not. I was just disagreeing with the perceived premise that because they were traded up for, they won't be successful. If Peyton had been 30, and expecting a full recovery, the Colts would have auctioned Andrew Luck to the highest bidder. And up until last year, I would bet his franchise would say he's worth the price.
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