I never said Fitz was a long term answer. However, Fitz is a lot better than Russell. Let's use the stats from nfl.com to explore this further.
Here are Fitz's numbers the past 3 seasons:
Season Team Passing
G GS Comp Att Pct Yds Avg TD Int Rate
2010 Buffalo Bills 3 3 52 85 61.2 595 7 7 2 99.9
2009 Buffalo Bills 10 8 127 227 55.9 1,422 6.3 9 10 69.7
2008 Cincinnati 13 12 221 372 59.4 1,905 5.1 8 9 70
That comes to a completion percentage of 58% and an average QB rating of 80. TD to Int ratio is 1.14.
Now here are Jamarcus's numbers the past 3 seasons:
Season Team Passing
G GS Comp Att Pct Yds Avg TD Int Rate
2009 Oakland Raiders 12 9 120 246 48.8 1,287 5.2 3 11 50
2008 Oakland Raiders 15 15 198 368 53.8 2,423 6.6 13 8 77.1
2007 Oakland Raiders 4 1 36 66 54.5 373 5.7 2 4 55.9
That comes to a completion percentage of 52% and an average QB rating of 61. TD to Int ratio is 0.78.
The above objective evidence shows that Fitz is significantly better. So just using simple stats pretty much refutes your argument about Russell being a better option.
Lastly, teams do not get out of a 10 year funk by signing someone else's first overall pick flameout and hoping that they suddenly become a Franchise QB. If you have a high draft pick and your talent evaluators feel there is a QB that deserves the pick, you have to roll the dice.