I don't understand layered tips either, but we can perhaps have some conversation about what's in between the layers of leather.
I'm merely assuming it's glue, since like I said I really don't understand the concept, need or effort in layered tips.
I'm also assuming if you took a blob of that glue between layers and let it drip out onto a piece of glass lets say, or Formica maybe or other hard surface and let it dry, the result, in my mind, after it dried would be something similar to a hard shiny spot of rock hard superglue or polyurethane or hard resin of some type.
Now I could be wrong already, but I feel safe in saying it wouldn't be leather. I don't know how many layers is normal but I know there are quite a few on some tips.
I took a few minutes and made this admittedly poor artistic attempt at a drawing of four tips. Brown represents leather, yellow .. glue.
The top two are layered, the bottom two represent non layered tips .
On the left, top and bottom represent exposed leather if tips were installed without crowning them. If it were done this way all that was exposed to the CB would be leather. But we know that's not how they are shaped.
On the right .. it represents crowning the tips and in the case of a layered tip, exposing this hard shiny glue to the CB. So ... a certain percentage of any contact between CB and layered tip happens on something OTHER than leather.
Not so on the bottom right. Even after crowning the tip ... all that is exposed to CB contact is pure leather.
I sure don't know if it matters ... sounds like it should.
I do know that most things on the mental side of pool result in ... if you think it matters then it does. LOL .. so I use triangle. :thumbup: