I would NEVER even consider this even if you restricted your potty to "P" only!
With #2 and TP in your gray water tank you won't be able to flush it get the solids out completely and it will never be clean again. Sloshing when traveling will empty your traps and you will get stink into the camper forever after.
Again; a very bad idea, IMHO.
Lou and Laura with Bella - German Short Hair Pointer
2008 GMC Sierra 2500HD Crewcab SB Allison Duramax
2010 Flagstaff 8526RLWS - Superglide 3300
HAM CALLSIGN - KC3FFW