I think its sorta funny that you use my post as your quote and basically address nothing in there other than to gloss over it. Also, your incorrect on your assertion that its only detractors that discuss Youngs legs/athletic ability. In fact I would make the claim that his supporters lean on that more than his detractors decry it.
The offense Young was in had a lot to do with his accuracy last year. Thats good for UT and their Championship, but honestly doesn't have much to do with his ability to be a top teir NFL QB. That type of offense is unlikely to be a big player in his NFL career. To be objective about his passing abilities I think we have to discuss things like only having to read one side of the field, ie the Quincy offense. And that gets into reading defenses, simplifing his reads last year was good for him and for the offense, but likely will worry NFL teams. College offenses are usually much simpler than NFL offenses, and Young had to have his college offense simplified for him. Reading Defenses is what makes the difference between a Peyton Manning and a Trent Dilfer, ie a very good QB and a middle of the road QB.
As far as Cutler you have to realize that his INT rate is acutally much lower than Youngs. Young was averaging 1/32 attempts, where Cuttler was averaging 1/51 attempts. Young's numbers should look better than Cuttler's. Young was on a good team with a lot of talent around him. His WR's, while below par for Texas's talent pool, would likely have been the best players other than Cuttler on Vandy. Texas is probably going to put 4-5 players into the NFL on offense Day 1 this year; Vandy probably won't put anyone other than Cuttler into the NFL this year. Texas doesn't have "pedestrian" players at virtually any position, and to say otherwise is idiotic. How many other teams in even the Big 12 would have liked having Texas's WR corps, or at least a player off of it? The TE is likely a day one pick. Basically you give Young credit for taking one of the two or three most talented teams in the NCAA to the house and dog Cuttler for being on one of the least talented Division I teams. Vince Young didn't single handedly lift UT to a national title this year, he had a big part in it for sure, but it definately wasn't Atlas putting the world on his shoulders.
I stand by my earlier statments and basically say that both Young and Cuttler have a way to go to be successful NFL QB's, much further than Leinart. They both have signinficant questions and those will only be answered by time.