Adding an identifier to return the number of mIRC instances running would be useful for scripters-- but that is not what is being asked here.
That said, if the suggestion was just for an identifier, that doesn't sound like a bad idea. In practice, though, it would be more complicated than that-- it's one thing to return the number of processes running, but it doesn't solve the problem of interacting with another process (i.e., activating the 1st process and exiting the 2nd)-- that would require more than just a new identifier, and now things become non-trivial.
