I, also, do not understand the "won't use the potty for solids" rationale. It is no different dumping a tank with only #1 in it that with both #1 and #2. One is not nastier than the other. I, also, do not understand the "won't put paper in the potty" rationale. Same argument.
Now, I agree with the "no feminine products" rationale. Those can stop up the system.
And, those "flushable" wipes, ain't! My Mother discovered that in her S&B house a few years back. Cost her a few hundred $$$ to learn that lesson.
Now for the part where this actually pertains to the OP. I don't do anything extra for either of my tanks. I do put a blue stuff packet down the toilet after dumping the tanks, although I am not really convinced that it helps anything. If I ever do spring a leak, at least I will be able to tell which tank it comes from by the color. I did add a
Tornado Tank Rinser to my black tank. When I dump at home using my Flojet Macerator, the tank rinser is an absolute necessity. When I dump at a dump station with the stinky slinky, it is less important.