I think it makes a difference whether its 10, 12, or 15 teams. The more teams there are, the more important postition scarcity and steals become. It's hard enough filling out 2B in a 10-team league. Imagine 15 teams! Ditto for steals. A guy like Crawford could put you halfway towards winning the steals category all by himself. With 15 teams, there are just that many fewer basestealers available, making the good ones more valuable.
I think that's in part why guys like Crawford, Renteria, Soriano, and Ichiro went so high.
Beyond that, you'll need to go deeper into the draft overall to fill out all 15 teams, meaning that your skill in picking sleepers and back-of-the-order guys becomes more important.
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