Most of us have experienced the kind of weird variation that John's example invokes.
On my current teams, the same Bobby Abreu is playing on two very similar teams, both in $80m leagues in RFK Stadium.
One of them has 174 PA, 3 HR, 15 RBI, a .215 BA and .322 OBP.
The other one is 113 PA, 4 HR, 22 RBI, a .337 BA and .398 OBP.
Given the same talent and similar context, the rest is just luck.
What drives must of us stir crazy is when bad luck sticks to one player -- or one lineup spot or roster position -- and won't go away.
I've used both Sandy Koufax and Joe Wood in their best years in the same rotation spot on one high-cap team that is in first place just barely. If either Sandy or Joe came anywhere close to expectations, the team would have a sizeable lead. Instead, Koufax went 2-7 and Wood is 1-8. Two other Joe Wood '12 iterations on other teams in the league are 7-5 and 7-7.
And then I get to wondering how much luck is involved in real life: when Barry Zito can't live up to his high-value contract or when a Walt Dropo comes along and has one sensational season and then falls into mediocrity. Luck in the form of random outcomes must be more of a factor in the sim than in life, but I wonder if luck isn't a much larger factor in real life than most of us are accustomed to thinking that it is.