Well, no, there is no such thing as a Four A hitter. That idea, as I understand it, envisions a "gap" between the majors and Triple A, with some players who fall into the gap. There is no such gap. In fact, there is a very significant overlap between the major leagues and Triple A. Many of the players in Triple A are better than many of the players in the majors.
The three examples you cite are three very different cases. Stenhouse never had 180 at bats in a major league season, so one would be hard pressed to argue that he got a full trial.
Frobel is a different [instance], in which I think there probably wasn't a real strong case that he was a good hitter to begin with. Frobel hit .251 at Buffalo in '81, hit .261 at Portland—PacificCoast League—in 1982. We would expect, based on those seasons, that he would hit .200, .210 in the major leagues, with a pretty ghastly strikeout/walk ratio—which is what he did. Then he had the one good year at Hawaii in 1983, looked like a better hitter, and fooled some of us into thinking that he was better than he was. But ... it was one year, 378 at bats, of performance that isn't that impressive. It wasn't enough, in retrospect, to conclude that he was actually a good hitter.
[Then] there are some players whose level of skill changes—drops—between two adjacent seasons or between two seasons separated by two or three years, usually because of an injury but sometimes because of some other factor. Frank Thomas is not the same hitter now that he was a few years ago; Tino Martinez isn't; Mo Vaughn isn't.
When those "disconnects" happen between major league seasons, we ascribe them to sensible causes—aging, injury, conditioning, motivation, luck, etc. Comparing major league seasons to minor league seasons, occasionally you get the same disconnect. Sometimes a guy simply loses it before he establishes himself in the major leagues. That's what happened to Komminsk, I think—he shot his cannons in the minor leagues.
I'm trying to make two general points here. Point 1: When there is a disconnect between a player's major league and minor league records, some people want to ascribe this to some mystical difference between major league baseball and minor league baseball. Unless you can say specifically what that difference is, this is akin to magical thinking—asserting that there is some magical "major league ability," which is distinct from the ability to play baseball. The same sorts of disconnects happen routinely in the middle of major league careers—not often as a percentage, but they happen. Everybody who plays rotisserie baseball knows that some guys you paid big money for because they were good last year will stink this year. It is not necessary or helpful to create some magical "major league ability" to explain those occasional disconnects between major league and minor league seasons.
Second point ... the creation of new knowledge or new understanding does not make the people who possess that new knowledge invulnerable to old failings. I can't predict reliably who is going to be successful in the major leagues in 2004, even if we stick with the field of players who have been in the major leagues since 2000. I can't do that, because there are limits to my knowledge, and there are flaws in my implementation of what I know. The principle that minor league hitting stats predict major league hitting stats as well as major league hitting stats predict major league hitting stats can be perfectly true—and yet still not enable me or you to reliably predict who will be successful in the major leagues in 2004, because I still have limits to my knowledge and flaws in the way I try to implement that knowledge.
Within the sabermetric community, a pitcher's strikeouts-per-nine-innings ratio has traditionally been taken as a good indicator of his overall performance. The A's starters in the last two years—and especially this year—have relatively mediocre strikeout rates but have done a very good job of keeping opponents from scoring runs. Is there anything surprising in this?
The question embodies four assumptions that I would be reluctant to sign on to. First, it assumes that statistics from a third of a season are meaningful. Second, it assumes that what is true of the individual pitcher must be true of the team. Third, the special importance that we attach to strikeouts has to do with projecting a pitcher into the future, not with evaluating the present. As to evaluating the present season ... the strikeouts are no more important than the walks, probably less. Fourth, the A's strikeout-to-walk ratio is better than the league average.
Right now, there are at least three teams—the Red Sox, the Blue Jays, and the A's—who appear to be employing a sabermetric methodology with some rigor. Even with more outlets for experimentation, are there still ideas you've proposed (either in terms of player evaluation or game strategy or organizational structure) that are still too radical for teams to consider?
Oh, certainly. Well ... it depends on what you mean by "proposed." I follow the maxim that you never start an argument you can't win. If an idea has no chance of gathering a following, I might sit on it rather than throwing it out to drown.