Telfon Patching is not magic patching, but used properly it is very good for bench shooting. In my opinion, one should not use an oil based "moose milk" to clean between shots. I have used 1 oz of Dawn, 15oz of alcohol, to 1 gal of water for years with better than average results. Other things to look at when using Teflon is the material itself, if the material is loose weave spraying Teflon on it won't help. The old Sansouce (sorry I misspelled his name), was very good, Texas 0.20 is outstanding. I have heard it is not available anymore, which is to bad. I believe that when the Telfon is on top of the powder for a long period of time (while waiting of a wind change) the powder does not change, because it in not wet or oily.
A couple of more things to remember, when using oversized balls and Teflon the crown can not have any sharp edges and don't use a short started that is to big. If one tears the patching while loading it will still come apart Teflon or not.
Michael