Have you watched Robert Griffin play?
I've watched a ton of RG3 and Tanny.
The only justification you can possibly have for calling RG3 "raw" is the system in which he played, which is unfair to the player himself. RG3 has everything that Ryan Tannehill has but much much more. Tannehill has a fast release while RG3 has lightning quick delivery, Tanny has a GOOD arm while RG3 has a CANNON, Tanny is accurate but forced bad throws in big situations way too often while RG3 is deadly accurate.
Tannehill can move in the pocket well and is athletic, but RG3 has good footwork and is also a track star.
Also, RG3 gets too much flack for being just a running QB, it simply isn't true. If you watch the kid play on passing downs, he stands strong in the face of pressure to deliver passes from the pocket with accuracy.
There really is no comparison between the two prospects, and with respect, you can't find anybody who knows anything about the draft who will tell you that there isn't a large drop off in talent at QB this year after Luck and RG3 go.
I'm not saying that Tannehill can't be good, I think he's very talented, but I'm scared off by his underwhelming and often game losing performances in the second halves of games. OK St. Arkansas, Texas to name a few. Even in the bowl game Tanny played against very sub par competition (Northwestern) he played a great first half, A&M got a comfortable lead, and in the 2nd half he went into the tank and threw a bad pick. IMO RG3 would have smoked Northwestern, lit up the scoreboard, and won by 30. Tannehill put up a boring (at best) performance.
I haven't even mentioned that for RG3 to take that God awful Baylor football program to a 10-3 record is a great accomplishment. I would have liked to see RG3 play in a big bowl game against a better defense, but because of the fact that Baylor's defense gave up 78 ppg, it wasn't going to happen.
At the end of the day, I think that Tannehill is a big project who will need many years to develop if it ever happens. I think that Weeden is a much more ready to go quarterback, and I'd much rather trade down for Weeden than stay at 8 or trade up for Tanny. This team has way too many needs, we need to trade down.