I have no doubt you have things titrated and calibrated to a a tee, greendoctor!
It's not practical or desirable to remove clippings on athletic fields either. One of the things many of us like about Fall nitrogen in the north is that it can hold us into mid-May or even just before Memorial Day without causing a flush of growth throughout Spring. You can easily tell by driving around which lawns have had early Spring N.
With regard to micros, there is one sand based football field here that typically needs a boost in mid-August. They do their own maintenance but I have made that application for them a couple times. That's probably the only place in my circle that would (has) test out as needing it. I've sprayed at low rates as window dressing for All Star Tournaments, District Soccer matches, etc. occasionally but never as a substitute for a sound fertilizer program and mowing practices.