WasWatching.com

First, some stats via the Complete Baseball Encyclopedia:

Runs Saved Above Average Leaders, Teams, AL, 2004:

RSAA                           RSAA    
1    Red Sox                     118   
2    Twins                       114   
3    Rangers                      91   
4    A's                          81   
5    Angels                       48   
6    Orioles                      16   
7    White Sox                     7   
8    Blue Jays                     2   
9    Yankees                     -41   
10   Indians                     -42   
11   Devil Rays                  -62   
12   Tigers                      -76   
13   Mariners                    -84   
14   Royals                     -115   

Runs Created Above Average Leaders, Teams, AL, 2004:

RCAA                           RCAA    
1    Red Sox                     119   
2    Yankees                     112   
3    Indians                      60   
4    Tigers                       53   
5    Angels                       25   
6    A's                           8   
7    Orioles                       3   
8    Mariners                    -21   
9    White Sox                   -42   
10   Devil Rays                  -49   
11   Rangers                     -50   
12   Twins                       -54   
13   Royals                      -90   
14   Blue Jays                  -146   

Yes, the Yankees pitching in 2004 was bad. There were really only four teams in the league with worse pitching that season: The Rays, Tigers, M's and Royals. But, as you can see, the Yankees had great hitting in 2004 - with only the Red Sox being just a tick better.

There are three teams to really note in the above charts: The Orioles, Blue Jays and Devil Rays.

The Orioles were just about league average in hitting and pitching. The Blue Jays had average pitching and no hitting whatsoever. And, the Devil Rays had no pitching or hitting, period.

The Yankees got to play these three teams 57 times in 2004. And, the average pitching of the O's and Jays were no match for the Yankees bats. And, as bad as the Yankees pitchers were, since Toronto and Baltimore did not have great bats, they could handle the O's and Jays batters. And, like I said, Tampa Bay was just terrible in 2004.

New York, that season, went 41-16 in those 57 games against the Orioles, Blue Jays and Devil Rays. That's a winning percentage of .719. Against the rest of baseball, the Yankees went 60-45 - a winning percentage of .571.

It was because the Yankees bats were able to beat up on the O's, Jays, and Rays - while the batters for Baltimore, Toronto, and Tampa Bay were not much trouble for the weak Yankees pitching - that New York was able to win 101 games in 2004. Without those three teams to feast on, the Yankees probably would have been a 90-win team in 2004.