Baseball hitters’ performance can be pretty accurately predicted based on previous performance, with adjustments for park effects, etc. Judging by the list of names, it looks like the ones that are known to have juiced raised up one level in the hierarchy - already great players like Bonds went up into previously unknown performance levels, already very good players (like Palmeiro) became greats, etc. Some names on the list were non-prospects who became just good enough to land a big league paycheck for a little while.
I understand the effect on hitters, but I still don’t get what benefit pitchers get, other than faster recovery between games - more muscle doesn’t make a pitcher’s fastball any faster or add bite to a slider.
It might not ONLY be strength...
I don't know whether it'd improve a slider, but I don't believe for a second it wouldn't increase the speed on a pitcher's fastball. Eric Gagne is Exhibit A.