I looked at all pitcher forecasts with at least 8 fan votes. There are 329 pitchers, which is 11 per team.
The total wins-losses is 2410-2036. Seeing that there are 2430 wins and losses available, Fans pretty much nailed the wins column. But, there are many losses unaccounted for. The win% comes in at .542, which is 7 losses too few per 162 games. (This is a similar story as with the position players.)
The average ERA is 3.98, which is pretty optimistic compared to the 4.3 that is the norm. Total runs per 9 IP is 4.28, which is 10% too low.
Total IP is 39310, which works out to 146 9-inning games. IP estimates are actually low by 10%.
Total WAR is 570, which is a similar story to the position players: multiply by 75% in order to get the number to make sense.