Brady is a freak. Being this good at 40 is amazing, and truly a testament to his professionalism. He truly has shown no signs of slowing down, he's actually getting better. I think he's got MINIMUM 2 years of quality football left. The thing is though, if your BB or RC, and you think JG is your franchise QB for the next 10 years, what does a first round pick mean to you when your giving up the next franchise guy? What happens if TB12 suffers an injury, or falls off a cliff (because like you said, they're is no historical precedent for what the man is doing).
They're the best run franchise in the NFL, and its not even close. If they think Jimmy is the next franchise quarterback, there isnt anything my team offer that is worth giving that up. If they don't think he's a franchise qb, they'll trade him for the best deal they can get.
Either way, Cleveland will not leave this trade with a franchise quarterback. Which is why i don't want to trade for him, especially not a first rounder.