Any structure, like layered 3/4'' plywood, comparing that to a 9 layered tip it holds up under stress.
Non layered tips need maintenance as they flare out with a player that has a swing like Kaci, Shaw etc, these guys can draw their ball 12-16 feet, Bergman also uses Zan layered medium tip.... layered is structurally a must until I can be proven wrong.
Bad miscue on a layered tip, tip can be attended to, bad miscue on single layered tips, in my past it blows out the side and needs replacement.
Efren does not have a big swing like Kaci/Shaw.