Skin Overlay Sort Layer Best Practices

Hi there, Simmers. Total newbie here, trying to educate myself about CC. I'm finding a lot of skin overlays that set the sort layer to 2200+...which I assume is why my other skin details (set at 2100) are invisible when simultaneously used. Is that assumption correct? (I use Tidy Details, so I can confidently say that it's not an issue of conflicting part types.) What are best practices for skin overlay sort layers? Tutorials here note that the standard for skin overlay is 1100...so why do CC creators set their skin overlays so much higher? Is there a benefit to 2200+ that I'm unaware of? I'd just like to understand before I go into Studio/CAS Tools to edit the sort layers. Thank you in advance for any advice and help!