I can't recall that I've ever utilized Bowa in a 70s Mystery game, but when I looked at the card and realized that it didn't correspond to the 1979 season, then my assumption was that the wrong season's card was on display. After analyzing Bowa's 1978 season, it looks like that is the card on display.
http://www.baseball-reference.com/playe ... r=1978&t=bHe hit three homeruns that year, 2 against lefthanders. That would seem to jive with a LHP N rating but a RHP W rating. He had 5 triples against RHP. I would have thought that the chance for triples would be greater than indicated, unless the card is factoring those instances when a double is stretched into a triple.
I don't know whether it is still available, but a SOM Online player, Yountfan, at one time had a spreadsheet showing how all of the players had performed in numerous 70s leagues. I would be curious if those seasons revealed to be Bowa's 1979 season were statistically similar to his actual numbers. My guess is that they likely do, and that the problem is that Bowa's incorrect card for the 1979 season is displayed.