Here's what I think....
We can't just look at the WinShare, WARP, and VORP totals of the 3 vs. the 1. Gom makes a good point about the preseason redundancy of Ellsbury/Crisp. Kilo makes a good point about Ellsbury being needed to play more than CF when Drew went down with injury.
So let's look at the total package contributions of who "would", or at least "likely would", have filled the spots vacated if the trade were made. Here are the combinations I'll use:
Kilo's Case - Wakefield (in lieu of Santana), Ellsbury, Lowrie, Masterson
Gom's Case - Santana, Crisp (in lieu of Ellsbury), Cora (in lieu of Lowrie), Moss*
Assumptions: Since Masterson came up from AA, the player who fills that role in system after him is likely replacement level, he needs no offset. Moss is included because I feel he would have been kept as the 4th OF had they traded one of their CFs - and, he's a good proxy for the other AAA internal options they would have gone to after the deadline had they still moved him to get Bay.
I'm using VORP, WinShares, and WARP. Keep in mind VORP results don't include defense, and I realize this creates in incomplete picture, but I like to the impact of defense and see if it agrees with my take on the players invovled. Also, I will prorate out playing times to match. Crisp's playing time will be brought up to Ellsbury's, Cora's up to Lowries, and for Moss, I will use only his Pittsburg totals because a) the two month window is about how long JE played RF for Drew, and WARP/VORP is league and park adjusted.
[table]Stat|Kilo's Case|Gom's Case|Kilo - Gom|Edge
VORP|80.2|100.6|-20.4|Gom
WnSh|41|42|-1|Gom
WARP|17.7|17.7|0|None[/table]
I agree with results for the most part. I can see the defensive improvement from Crisp / Cora to Ellsbury / Lowrie being worth 20 runs over the amount of time they played. The other two stats pretty much show it to be net zero. Santana is great, best pitcher in the game right now, but you are talking about 3 good players in return. The absolute best position players will put up double digit WARP totals through their prime. Guess how many the last dynasty had, the '96-'00 Yankees? One, Jeter in '99. Guess how many years they had the best pitcher in baseball? None. But they were solid from top to bottom. No easy outs. A deep rotation. They played good defense, ran the bases well, grinded out their at bats, and pitched well up and down the pitching staff. You don't get there doing 3 for 1's.