While doing all the work for the lineup database, I've made sure to doublecheck the stats. I don't worry about the starters, because I figure that they got those right. But what I do is check the total number of substitute appearances for each team in each season, then I count the number of total subs in the lineups. If they don't match, I have to go through and figure out where the discrepancy is. It's happened a number of times. For your amusement, and for any fellow stat guys out there, here's a list of MLSnet mistakes:
1) First of all, the entire 2001 season is messed up. You can't view any of those match reports. That's just inexcusable. Thankfully though, there's Internet Archive.
2) 1996: Andrew Restrepo missing from season stats page.
3) 1997: Cle Kooiman missing from playoff stats page.
4) 1998: Alberto Montoya missing from season stats page.
5) 1998: Joey Martinez missing from playoff stats page.
6) 1999: David Winner and Caleb Porter missing from season stats page.
7) 2000: Josh Wolff appearance missing from playoff stats page.
8) 3/28/98: Welling Sanchez sub appearance missing for Metrostars.
9) 4/29/98: Mo Johnston sub appearance missing for Kansas City.
10) 5/01/99: Zak Ibsen sub appearance missing for Los Angeles (pretty sure the date is correct, but not 100%).
11) 9/12/99: Andy Williams sub appearance missing for Columbus.
12) 9/19/99: Jim Rooney sub appearance missing for Miami.
13) 8/25/01: Colorado own goal later credited to Chris Carrieri.
14) 5/10/03: Tim Regan sub appearance missing for Metrostars.
15) 7/12/03: Joselito Vaca sub appearance missing from Dallas.
16) 8/16/03: Tyrone Marshall sub appearance missing for Los Angeles
17) 8/30/03: Pat Noonan sub appearance missing for New England.
18) 8/30/03: C.J. Brown sub appearance missing for Chicago.
19) 7/10/04: All subs missing for Columbus & Dallas.
20) 4/30/05: Gilberto Flores sub appearance missing for Metrostars.
21) 6/19/05: Matt Taylor sub appearance missing for Chivas USA.
22) 7/16/05: Mike Magee and Abbe Ibrahim sub appearances missing for Metrostars.
23) 9/24/05: Ian Russell sub appearance missing for San Jose.
I know they don't have a huge budget, but this is unacceptable. I'm going to email them this list, so let's see if anything gets fixed.
EDIT: Oh, and I also forgot to mention there are a number of broken links in the old match reports.
EDIT 2: Looks like I found a few more. I should mention that for the more recent games, you can usually find the sub in the matchtracker/pbp. They just don't show up in the match reports.
Also, the lineups for the US Open Cup games often times aren't on the match reports on MLSnet. I get those from usopencup.com.
24) 4/23/05: Ned Grabavoy sub missing for Los Angeles.
25) 5/8/05: Michael Umana sub missing for Los Angeles.
EDIT 3: Should be the last edit, because I'm done with all the teams now.
26) 5/8/05: Alain Nkong sub missing for Colorado.
27) 7/16/05: Hunter Freeman and Guy Melamed subs missing for Colorado.
28) 9/3/05: James Riley sub missing for New England.
29) 9/24/04: Kenny Arena sub missing for Metrostars.