Let's close the numerical books on the first year of the Worst Trade Ever. First, a straight-up comparison of the two left fielders involved, which reveals that we paid 3.4 times the salary of Juan Rivera in 2011 for essentially the same production from Vernon Wells:

NM   G   PA  AB  R   H  2B 3B HR RBI SB/CS BB  SO  AVG  OBP  SLG OPS+ oWAR dWAR  WAR $mil
VW: 131 529 505  60 110 15  4 25  66  9/4  20  86 .218 .248 .412  83   0.2 -0.5 -0.3 $18.0	
JR: 132 521 466  46 120 23  1 11  74  5/3  43  76 .258 .319 .382  91   0.3 -0.8 -0.5  $5.3

More important than the $12.75 million cost overrun in 2011, of course, is the $63 million owed Wells over the next three seasons. If we assume an average Angel payroll of $150 million for the next three years (it was around $142 million this year), a full 14% of that will be paying for the pleasure of watching a rapidly aging player who was no better in 2011 than Juan Rivera -- a soon-to-be free agent who will be lucky to win a $2 million, one-year contract in 2012.

There is still another cost associated here: Phenom Mike Trout made his major league debut on July 8, and from that point through the end of the year was a much more valuable player than Vernon Wells, putting up a Wins Above Replacement of 0.9 over 135 plate appearances. During that period, Vernon Wells had twice the amount of playing time -- 272 plate appearances. If the left fielder sucking gas and blocking Trout had been Juan Rivera instead of a former All-Star in the first of a 4-year, $81 million contractual obligation, Juan Rivera would have been benched, and Mike Trout would have launched his career as a starting outfielder. If you would have given Mike Trout the 272 PAs, and Vernon Wells the 135, and they had played at the same rate, the team would have received around 1.7 WAR from the left field spot the rest of the year instead of the 0.7 we got. One extra win might not sound like much, until you reflect on how long it took this team to be eliminated.

Now let's bring the pain: Mike Napoli, Jeff Mathis, Hank Conger, and Bobby Wilson.

NM   G  GC  PA  AB  R   H  2B 3B HR RBI  BB  SO  AVG  OBP  SLG OPS+ oWAR dWAR  WAR $mil
MN: 113 61 432 369  72 118 25  0 30  75  58  85 .320 .414 .631 171   4.9  0.6  5.5 $5.8
JM:  93 91 281 247  18  43 12  0  3  22  15  75 .174 .225 .259  37  -0.5  0.2 -0.3 $1.7
HC:  59 56 197 177  14  37  8  0  6  19  17  37 .209 .282 .356  80   0.7 -0.4  0.3 $0.4
BW:  57 47 127 111   5  21  8  0  1   8  10  16 .189 .252 .288  53  -0.2  0.1 -0.1 $0.4

Before you say "Duh, Arlington!", remember that Napoli hit even better this year on the road: .332/.414/.663. To which Mike Scioscia might say, "Well yeah, but Napoli only caught 61 games!" Fair enough -- since many of us would have simply DFA'd Jeff Mathis rather than pay him $1.7 million to be one of the worst hitters in the history of major league baseball, let's simply subtract his 281 plate appearances from 2011 and replace them with Napoli's 243 plate appearances as a catcher:

       PA  AB  R   H  2B 3B HR RBI SB/CS BB  SO  AVG  OBP  SLG OPS+ oWAR
Real: 583 516  38  99 27  0 10  48  1/4  40 125 .192 .252 .302  56   0.0
Fake: 545 478  64 132 27  0 26  69  2/3  56  92 .276 .354 .496 144   3.5

Yep, that's the difference between playing Mathis half-time and playing Napoli half-time. I'll let you catch your breath. Though the OPS+ and offensive WAR numbers in the Napoli scenario are a bit eyeballed, they're in the ballpark. Long story short, we would have gone from having one of the worst lines of offensive production from any position on any team, to having one of the best. For $4.1 million more than we paid in 2011 at the catching position, we would have received a total of 3.5 WAR at the position instead of -0.1.

So let's add up the alternative scenarios. If the trade never happened, Jeff Mathis and his -0.3 WAR got DFA'd, Mike Napoli and his 3.5 WAR at the catching position remained, and Mike Trout started playing full time on July 8 with Juan Rivera reduced to a bench role ... we're talking about a net gain of around 5 Wins Above Replacement in 2011, and that's not even counting Napoli's extracurricular work at 1B and DH. How many games did we finish out of the playoffs? Five. Subtract Napoli's 5.5 WAR from Texas, and add our 5, and that 10-game spread in the American League West looks a whole lot different. All this for $8.65 million less than we paid out in 2011, and only a one-year Napoli arbitration raise in 2012 instead of a $63 million Vernon Wells black hole from 2012-14. You think maybe Arte wishes he had a spare $25 million lying around in an offseason where Albert Pujols and Prince Fielder are available?

Now, of course it is true that we cannot assume that Mike Napoli would have ever hit .320 in an Angel uniform, and perhaps it is unreasonable to assume that Mike Trout would have played at the same rate of effectiveness had he gone full time out there. But what we do know is this: At the rate these players played on the field in 2011, we would have been at least 5 wins better off for considerably less money.