That answers the question completly. Thank You!
Ed
If, for instance, I am going to apply my Photoshop work to something 10'x 15', I might do the Photoshop work at 10" x 15", or even 2"x 3". Then, when the texture is created, I would set the feature size to 15', which would cause the texture to scale to my 15' dimension, regardless of what scale I was working in.