Sorry I did the math incorrectly.
I corrected it below - but feel free to check it.
By trading Romo, we reduce our chance for winning the Super Bowl from 37.5% to 25%.
These percentages are arbitrary and just make it easier to do the math
The exact numbers do not matter that much as long as you assume a Romo-equipped Broncos is just as dangerous as the Patriots.
I assume we have a 50% chance of getting to the Superbowl (actually this does not matter to the final number).
I assume Patriots have a 50% chance of winning the AFC and I gave them 50% chance of beating us.
.I assume no other team in AFC has a chance against us to keep the math simple.
If we do not trade Romo, our chances 37.5%
50% * (100%*50% + 50%*50%) = 50% * 75% = 37.5%
If we improve the Broncos by trading them Romo, then the AFC has now 2 equally dangerous teams with an equal chance of being the AFC champion.
Now with Broncos and Patriots being equally dangerous, there is an essentially 100% chance that the AFC champion is 50% likely to beat us.
So the math becomes 50% * (100% * 50%) = 25%.
Counter Argument
@bkight13 has already shown we have enough $, so the cap argument is not valid.
One can say we can get a 1st round pick from Denver to improve the defense.
However, keeping Romo insures either Romo or Dak is the backup which protects us from QB injury.
Do these cancel out?
May be or may be not.
But the "dont improve your enemy" argument is obvious.
