[jtur88]

What you did not account for, though, is the fact that a team with a leadoff double will often give up an out to get him to third, obviously underscoring the advantage of stretching the double to a triple.

I'm assuming that a batter hits a ball that could be stretched to a triple with equal frequency irrespective of the number of outs. If the team strategy is so often to give up a "productive" out to move that runner to third, it would certainly seem that the batter would respect that philosophy and try more frequently (rather than the prevailing less frequently) to get there without necessitating that following out. Granted that there is the risk of losing the baserunner entirely, but the risk remains the same regardless of how many outs. However, the reward increases significantly with one out,, when weighted against the constant risk.

There is, in fact, the oft-repeated adage, that you don't make the first or third out at third base. But hitters violate that, by electing to stretch triples more often, rather than less, in that situation.