From the article comments thread:
I made a similar argument with my softball team: Imagine there are a couple guys who want to play but they can't stand each other and won't play together, so we have to choose only one. One player (McGwire) bats .500 but every hit is a home run. The other player (Gwynn) bats .750 but every hit is a single. Which player would you choose?
By most metrics (OPS, RC, fantasy baseball points, totals bases, etc) McGwire rates as a much better player. Intuitively, wouldn't you rather have 2 HR than 3 singles?
But what if you had an entire team of that player. A team of McGwires would hit 3 HR per inning and score 3 runs. A team of Gwynns would hit 9 singles each inning and score 6 runs - twice as many!
The point I was making was the value of On Base percentage. If you are adding one player, add a McGwire. If you are building a team, get 9 Gwynns.
Not exactly on topic-
There has to be a tradeoff between bat speed and bat control. The ultimate contact play is the bunt, when the bat has essentially zero speed. Not only does it give the batter maximum control over placement of the bat in the zone but it also lingers there for as long as the batter chooses. As bat speed increases more energy goes into accelerating the bat and less is available to control the placement. And the as the bat sweeps through at faster speeds it is in the hitting zone for shorter periods of time, so the timing of the swing becomes more critical too.
Ideally a quicker bat (as Bill points out not the same as higher bat speed) gives the batter more time to observe the pitch and decrease his margin of error in the swing. But a slower bat speed just might allow for some in-swing corrections that are impossible with an all-out swing.
And, if I recall correctly, several years back MLB actually reduced the maximum diameter of the bat barrel. It was just a fraction of an inch, and it drew no criticism in part because batters were no longer using the largest allowable size. Hitters wanted lighter bat weights which could not be attained with the old maximum barrel size.
[Dr. D] Ichiro did seem to "veer" the barrel of the bat as the pitch came in. Much tougher to do when you're launching the bat from your wallet and spinning out into the on-deck circle :- )