One thing John Krieger says that doesn’t seem to make sense is saying abrasive elements embedded in a nylon brush being pulled across a crown can damage it. By that logic, every brush stroke may be damaging your lands or grooves. He does clarify “1000’s of times probably not 100’s of times” referring to the potential for damage with nylon. Seems he’s just erring on the side of caution.
I noticed Frank Green recommends against using any brushes.
Either way, I clean when it needs it now and haven’t noticed any difference except a lot more time shooting than cleaning.