Anecdote here, not evidence regarding DMB:

I know that older games like Strat-O-Matic based their cards against league-average opposition, so late-inning pinch-hitters like Gates Brown who would face almost exclusively the best relievers of his day will underperform, because he would have a card programmed to hit .370 or whatever against league average pitchers, then have to face the cream of the crop in Strat game situations. I haven't heard of anything that would change that basic philosophy in games of more recent vintage, however.