I've explained it very well in my feature request here.

Picture adding a block in WED and texturing it. By default, the texture scale is 1. If I drop it down to 0.25, it simulates exactly what I'm after with models. Look at the screenshots in this example to help understand. To give some examples:

1. I have a model that is 16x16 quants and a single skin of the size 1024x1024. When I select this and if it's the only thing there, the area the skin vertices spans is the entire 1024x1024 texture space and it looks so fine, there's no meaning in using it. If it was a series of 16x16-quant squares in a 2x2 grid with only one selected, the skin vertices would then span 512x512 in the corner of the square I selected. If I have a part of a model far out (like 16384 quants) and I'm trying to texture a 16x16-quant area, the area covered on the skin map would be so small, you'd have to zoom in to at least 4x (and even there it's very tight) in order to reliably manipulate it.
2. Now let's say I have a model that is 4096x4096 quants in a square with a texture size of only 64x64. When I create the UV map, the texels are just downright huge (as if setting the texture scale on a WED block to 64!). No matter how it is adjusted, the entire texture area is used without any overlap. If I raised the size of the texture to 256x256, it'd use a 256x256 area instead giving a 16x texture scale (still huge). If I used a 16384x16384-quant model square on a 64x64 texture, it'd still use the 64x64 size making a WED texture scale equivelent of 256. Imagine seeing each texture pixel as 256 quants. It doesn't even look like anything usable. Now, if I moved the skin vertices to 4096x4096, the size of the original model, the texture would tile 64 times and would look like WED's texture scale of 1. In my case, what I'm after, would be moving them to 16384x16384 to get the 0.25 scale (WED equivelent) which would look very fine and is what I'm after. The further apart the skin vertices are, the finer the texture appears. The spring as shown in the 4th screenshot in my most recent reply above uses this 0.25 texture scale. If a vertex was at (8, 8), I'd place the skin vertex at (32, 32) and otherwise just multiply everything by the same scale factor. With odd positions, like 3.2894417, this is where I need to use calculator.

Why can't I just use the scale tool? It's very inaccurate and doesn't scale properly (and when things are stitched together, there is a noticable texture misalignment.

The concept is easy to use - just multiply the positions of the vertices as per the mapping type for placing the skin vertices. Someone else gave me a small plug-in that otherwise does this, but skin vertices aren't affected at all, but the actual model's mesh is (which is helpful). It's the default system for positioning the skin vertices that's the problem - it scales covering the area of the model to the area of where the object is placed and it causes very strange values to occur in very unusual ways and the scaling is set on each axis rather than being proportional causing odd distortions. I don't know if the user who gave me that would mind me posting it as a reference for manipulating the skin vertices. It seems as if the SDK doesn't even allow that and it only seems to apply to that of the 6.31 version.