I honestly thought it was a myth, an urban legend - until today.
Running the Sycrus grind as AST (to at least give me something engaging to do) I had another AST co-healer.
He overwrote aoe Balance with aoe Spear then aoe Bole. Not once. Twice.
I hope I was being trolled. Really I do. Not that it matters in the long run - but you have to question how people can do 70 levels of any character have no grasp of the basics.
