I am pretty new to wet shaving and I have a quick question. 9/10 times I use a glycerin based soap like VDH. Every now and again I'll use a cream like Proraso and I even got a chance to try some Tabac. When I used creams and tallow based soaps, I noticed that they turned my razor and brush handle really white, and made my brushes dusty. An expert brush maker told me that the white dust is really bad for the brush, so it makes me hesitant to use creams and tallow soaps. What is it that causes this residue? And how can I rinse this residue out of my brush without having to go through the brush cleaning process? I have some exquisite RV brushes and I don't want them to get damaged!!! Thanks guys!