Layer blend per bone weight min/max?

I wonder what the min/max of the weight. It was hard to tell if the ratio of 0 to 1.

I would also like to know how to achieve that. A proper blend per bone with some sort of a per bone opacity or weight.

In the UE4 documentation says:

The number of levels down the bone hierarchy used to transition from the BasePose to the blended output. For example, if BlendDepth is 5, the fully blended output will begin 5 levels down the hierarchy from the starting bone. So, if performing a blend with a 0.5 BlendWeight, the first level will perform a blend with a 0.1 weighting, the second level will perform a blend with a 0.2 weighting, and so on until a blend of the full 0.5 weighting is performed at the fifth level and all levels after that.

However this doesn’t seem to be working very well on my end.