Sometimes you know you have a certain card by a player, or perhaps a limited range of cards with similar characteristics, but the player's performance is very different. Maybe they're hitting or pitching better or worse overall, or not hitting lefties when they should, or whatever.
Do you reach a point where you start managing the performance rather than the card? For example, one year knew I had Dave Collins in his 1984 season. It's his best year, .801 E. So his platoon ought to be balanced. But in practice he killed RHP and didn't hit lefties much at all. He had a .893 OPS vs RHP (in 119 AB) and .660 OPS vs LHP (in 60 AB). Collins was my backup OF, but, as you can probably guess, after a while I started platooning Collins vs RHP and limiting his AB vs LHP. I found it hard to resist doing this even though the card told me their performance should be even. This platoon differential was surely just random, and his overall OPS of .816 was not far from the OPS on the card. Still, I've made similar moves with other players as well. Sometimes, I've managed lineups this way, batting the better performer higher in the order than the better card.
So, sometimes I find it hard to resist the karma of the rolls. Am I just nuts or do other managers do the same? I do try to avoid dropping a good card because of bad performance, but it's hard to resist having it affect my lineup choices....