You seem to be arguing about the semantics of the terms being used. It really doesn't matter whether it's called error handling, exception handling, or anything else. It's all doing the same thing - which is not merely debugging.
Off the top of my head I can't think of any situation in mIRC in which error handling code isn't triggered by an actual error. Errors are neither good or bad, it's what you do with them that counts. For instance trying to write to a file that is in use by another application is an error, however as long as my code catches that error and either does something else or reports to the user that it cannot complete the requested task it isn't a bug and isn't a bad thing.
