Here are three items I will combine to make a point.
1. As a teenager I taught myself to bat lefty in addition to my natural righty primarily because Mickey Mantle was my favorite player and Mickey is the greatest switch hitter of all time. I wasn't very good but when my cousin Richie pitched to me I batted lefty. After not playing for several years I decided to play softball, both fast pitch and slow pitch. At the first practice I stepped in lefty and did not hit well. Embarrassed, I switched over to my natural righty and hit fine. Hey, there were no curve balls. I'm almost 64 and it finally dawned on me that if I had any brains back then I would simply have practiced batting lefty for a couple of weeks and I would have regained my form. Then I could have spent a couple of decades taking advantage of what may be the most stupid baseball rule on that long list: lefty batters get to stand two steps closer to the bases. It's an advantage not just on infield ground balls but also on long drives when trying for a double or triple.
2. While playing for the Angels 1964-1970 hot shot bonus baby righty slugger Rick Reichardt made his manager Bill Rigney who managed the Angels from their inception in 1961 into 1969 a little nuts by suggesting that he learn to bat lefty in order to take advantage of certain ball parks. You know, bat righty in Fenway Park, lefty in Yankee Stadium regardless of which arm the pitcher used. Most people thought Reichardt was nuts. However, Reichardt may have been ahead of his time. Reichardt wanted to take advantage of another stupid baseball rule that allows for non-uniform playing areas.
3. This week on the MLB network program Clubhouse Confidential consultant Vince Gennaro spoke about batters who had the biggest differences against righty or lefty pitchers. He then broke it down for lefty batters, not just against lefty pitchers, but against different types of lefty pitchers, particularly "killer lefties" like CC Sabathia v. soft throwing southpaws like Mark Buehrle who do no dominate lefty batters. Against killer lefties Johnny Damon has a pretty low OPS, about .550, and Hideki Matsui is better against the killer lefties than against the softies at about .850.
About 66% of plate appearances are against righty pitchers, so the managers usually want lefty batters up in those situations unless they have Albert Pujols. It could be that all batters should learn to switch hit, if only to take advantage of certain situations including:
1. Bunting. When sacrificing, why don't righty batters, especially those quaint NL pitchers, switch and stand closer to first base and put more pressure on the defense. Do you think a good righty bunter cannot bunt lefty? I'd be shocked if they could not learn.
2. Other factors being roughly equal, why not try a Reichardt and switch by ball park. Suppose your team needs a home run in Yankee Stadium. Switch over from righty to lefty and try to jerk one out.
3. Get that two step head start running out of the batters box on a batted ball. How many times have we Yankee fans seen righty Derek Jeter thrown out at first on a VERY close play? How many of those might Jeter have beaten out had he been batting lefty? Jeter is a perfect example of a guy who should have been switch hitting. His home park is a disadvantage to righty batters and Jeter has speed. Why not?
4. Lefty batters could switch to righty against those killer lefties. Johnny Damon, are you listening? What the heck? You couldn't hit much worse.