Can NPC Trainers DELETE/REPLACE a spell?

[FrostyC]

Is there a way to make my trainers replace a spell that is already learned by a player? Or delete one spell from them & add another?

Say for instance, I want a rogue to train a spell like Uber Stealth, can I have the trainer take away their regular Stealth ability when they train it?

This is for Trinity Core on 3.3.5a. Any help is much appreciated. Thanks!