I use brown toner in the following way:

1) take a completed print - which means fully washed but still wet OR rewet dried print in water
2) put it in working bath of the toner
3) complete wash

I don't do the post toning hardener (which Kodak recommends using Kodak Professional Fixer which contains hardener) step or the following HCA step. Using all the paper I have, the emulsion doesn't get soft enough to be a problem. I can do anything I normally do and no damage.

Brown toner has a peculiar property of toning FASTER in more dilute solution. That means if you take print out of the toner bath and put it in wash, it will TAKE OFF and basically tones to completion. Very weird but it happens in reality. If I didn't want to tone to completion, then I soak it in 10% solution of Sodium Sulfite (basically an extra strong HCA) to stop the toning, then wash.