The amount hat the idel mix generates to a running engine at full chat is insignificant.
The reason for the lean settings is to please eco warriors, it does not work though.
Set it at 2/2.5%, and it will be a world of difference, even if set at 0.1 it will do no harm just drive like a bag of crap low down.
If you imagine the air going into your engine at ilde then at full throttle you will see what I mean the idle cicuit and co is nothing to do with main running and will have next to no effect
tabetha