Mistwolf is correct. The AR likes lube on the bolt especially. I've found that of all the lubes, expensive and in-expensive I've tried, FireClean has worked out the best. It is expensive, but truly lives up to my expectation.As you point out, the AR does not need to be lubed so much it's dripping. However, the problem with excessive lube is that it's messy, not that it's detrimental to function. Oil is supposed to trap and suspend gunk so that the gunk can be carried away to keep the moving parts moving. If the oil is getting thick with gunk, add more oil. It will thin out the thickened goo, wash away the gunk and keep the rifle humming along until it can be cleaned.
Nothing wrong with starting off with just enough oil to get the job done. But don't be afraid to give the BCG a good squirt to keep things running smoothly and don't worry about over lubing an AR. It won't hurt thing
I only use it on DI guns because the carbon build-up and heat on the bolt justify using an expensive lube. It seems to cut down on cleaning too. I know you've heard these claims before, but this seems to be more truthful with FC.
FC seems to make things run smoother on a DI gun. After using it for a couple cleanings you will notice that it seems to reduce grittiness when operating the charging handle after having fired a couple hundred rounds.