Well I don't know about cocky as being statistically accurate.
OUt of the 50 Fast Forwards used on this show, almost all of them have put a team in First place.
And out of those that didn't one was due to a team not going to the Pit Stop and taking close to 8 hour break (season 1's Guido's).
Season 3 had Dennis and Andrew who are over 27 hours behind the lead teams getting to London where the Fast Forward is, they end up nearly half a day still behind and are eliminated.
Season 4 had Monica and Sheree who were in group #2 (being two hours behind group #1). When they are the last of group 2 to get on there way they take the Fast Forward, they come in 4th beating one team from group 1 and end up only gaining 30 minutes over the best performer in group #2 (kelly & Jon).
Season 5, Brandon & Nicole go to the Fast Forward and choose not to do it.
So statistically speaking any team on even footing with the rest of the group (they actually have a small lead) should be able to get teh Fast Forward and keep its lead.
Included people having trouble, getting lost for an hour, and just going slow).
So I certainly can't blame the guys at all, and even working as a group for the whole leg (ths being forced to be as slow as its slowest player) tehy still manage to beat all but one team.