If you are going from point A to point B and the e

If you are going from point A to point B and the end points haven't changed, why should a refining of the process change the patent?  I do realize, though, that practicality and reality don't align that often when dealing with government agencies so my statement above may be in error.

Whatever  endpoint B is, I am sure the patent will wrap up any and all uses for that product.