Hey, I have found that the leadership rating to do this in my leagues(not guranteed i guess, but what i have noticed in many years):
Leader-Gets "hot" toward the last month of the season. He produces much more toward the end of the season from the beginning.
No leadership-Get off to a quick start, but fades in the final month of the season.
I noticed this with allstar calibur players who i followed in my leagues. Most notably Babe Ruth. He had a great leadership rating. So he would mostly hit around 15 HR's the last month of the season compared the the 8 he hit during the others.
Hope this advice is true, if not....Sorry
Aar