Dealing with Surface Parameterization, Alex Alvarez
If your somewhat new to texture mapping, you should read up a little on parameterization as it often causes a bit of confusion. Basically, remember this: just because two surfaces look identical in regards to the number and placement of spans in u and v, it does not mean that a texture map will wrap itself around the surfaces in the same way.

Above we have a single surface NURBS head which I modeled from a primitive sphere. Modeling organic shapes by inserting isoparms and pushing/pulling points is a common technique which is very quick and works well when a patch model is not needed. But, notice in the above image how the texture map of a checker pattern is not evenly placing itself along the surface. Basically, when you use the above technique to model, you will end up with funky parameterization. So in order to get a lot of texture detail in the neck, you may end up needing a 2k texture, at least with this model... which is a little big for certain applications.

So what I tend to do to address this issue is quite simple, thanks to a tool added a couple versions back in Maya: Edit Curves/Duplicate Surface Curves. By selecting the above surface and invoking this tool, I was able to, in one step, duplicate all the curves in the V direction which is what we see in the above image. These curves can then be 'lofted' together.

With the curves selected, I then used the 'loft' tool, with the 'Chord Length' option checked. In the above image, we see how the same checker pattern is mapping itself to surfaces before and after (the head on the right) using this method. Chord length sets the parameterization of the surface so that a texture map will evenly place itself regardless of isoparm placement.