The mesh isn't inherently bad. The distortion is likely due to either [A] Using cylindrical mapping on a tube-like shape which has considerable variation in radius, or [B] The mesh was originally a cylinder and mapped as a cylinder, but was later re-shaped, in which case stretching out that upper portion of the tube also stretched the UVs.

UV-unwrapping would lay the mesh surface out like a bearskin rug, giving a flat 2D projection of the 3D surface. Almost every Poser doll is UV-unwrapped; that's why their templates look like a bearskin rug. UV unwrapping is the hot ticket for dolls, clothes, organic shapes like tree trunks/branches, etc. To do this, you need a UV mapping utility which has UV-unwrapping. I use UVLayout; there are several other unwrap capable mappers.

Poser 12, in feet.  

OSes:  Win7Prox64, Win7Ultx64

Silo Pro 2.5.6 64bit, Vue Infinite 2014.7, Genetica 4.0 Studio, UV Mapper Pro, UV Layout Pro, PhotoImpact X3, GIF Animator 5