With my cams I was RUNNING SUPER SUPER RICH on the bottom end @ idle esp...on other cars (with stock TB the measrure is zero BTW) I found out that due to the size of my butterfly plate in the TB that my throttle was not returning all the way to zero% so I moved the throttle stop in by twisting it with some vice grips (it is a screw) I got my TPs to measure 5.7% @ idle now and my car launches off the line SO MUCH BETTER!!! If I mod the throttle cable plate by shaving some more off it I think I can get it to zero. I think it turns out that if this is all incorrect (assuming fuel maps in the ECU are supposed to measure idle fuel mix @ 0% throttle) that my car is running really rich @ idle (which it was) and lean on the top end (which voltages tell me so) The motor thinks it has throttle @ idle and gives ectra fuel to the ECU but since the butterfly plate is closed hardly any air is getting int he motor and you get a rich mix. It goes oppsite on the top end of the RPM scale. The ECU only sees 75% while the butterfly is all the way open @ WOT and not enough fuel is getting in the mix b/c more is getting in than the ECU thinks.
If you have a bored TB you should really check to see if this is the case. Is your TB stock or not? I would be curious to see if there is a TPS % difference @ idle with a stock vs. bored TB.

Does any of that make sense? I am curiouse to hear what others have to say ...not sure if I am right or not. But I think I might be.