Byline: Gene Frenette, Times-Union sports writer
More than ever, I'm convinced the best tool to keep handy in observing the sports world is a slide rule. Because in no time at all, so much -- the image of Mark McGwire, a team's RPI, David Duval's golf game -- can change.
The magic number is now 180, as in the degrees of turn. What seemed preposterous not so long ago has moved entirely in the opposite direction. We probably should have seen this coming. Ever since the Boston Red Sox erased that 0-3 deficit to the New York Yankees in the American League Championship Series, a lot of things aren't like they seemed.
Take McGwire, who enjoyed practically a free …