Classic tailpiece

[hardryde_mando]

Hey, this question might sound really stupid, but I'll ask it anyway. Does anyone know the purpose of being able to hook the unwound strings in 2 different places on classic tailpieces?

[mandroid]

FAQ

The winding of the loop has proven it self to slip, occasionally, and the tail-piece was designed
to accommodate this fact.
some tension load sharing
adding the last tight windings the ones directly across the string , have helped .

[red7flag]

The string curls around the first hook and hooks on the second. This helps keep the string from popping off. I learned this when I tried just using one hook and the little rascal just popped off while tightening it. Then I found my self saying "Ah I see." Because it works.
Tony

[Givson]

In the early years of the 20th century, strings did not come with pre-tied loops at the end. The musician had to tie his own loops. These user-tied loops tended to slip on the unwound strings. Thus the two hook arrangement for the four unwound strings.

[MikeEdgerton]

Frank Ford explains it here as well on frets.com.