In my opinion, the reason(s) why a player would want to hit the ball hard (normal swing) with a runner on 3rd and 0 outs, are pretty obvious. a) The player isn't necessarily trying to hit a home run, but if it is hit to the outfield (e.g. fly ball), a hard hit ball is more likely to be deeper in the outfield and give the runner a better chance at scoring. On a line drive to the outfield, it has a higher chance of landing. Any infield hit will in theory be harder and thus make it more difficult for the infielders to get to, thus increasing the chances of scoring the runner from third. If Dozier it's the ball 102mph between infielders, nobody is getting it. However, if it's a 72mpg bouncer, it allows the infielders more time to field the ball. Perhaps the runner still scores, but it's a a guarantee the runner scores if it gets by the fielders into the outfield. As for Dozier specifically, I do recall him bunting over a runner to 3rd base from 2nd base the other day, so he's not always going up there hacking away. I'm pretty sure they know what they are doing out there. It's just a matter of determining the risk/reward of each decision.