Just the same, I'll take my empirical evidence over your conjecture anyway. If you've been running tubeless and have magically avoided a clogged stem or that occasional Stan's-blast when you attached the pump head, good for you. I run tubeless on 3 bikes, have 25,000 miles between them in 3 years, and buy presta cores by the ten bag. Does putting the stems at 4 or 8 help, when I remember to do it? Yes, yes it does.