I’ve come to the conclusion that Archer either doesn’t want to do it, or isn’t smart enough for toilet training.  Lana is very smart and even after we took the insert out of the toilet she has gotten up on it and started to use it.  She might even use it regularly if we can catch her doing it and reward the behavior.  Archer was at the point where he wouldn’t use a full insert that was clean litter.  That was a bad kitty and bad sign.