Don't quote me, but I seem to recall from years back that there was some comment on how mIRC handles scripts and it was said (I think) that the events (and aliases) are loaded up so that mIRC knows they are there and does not need to read every file every time something happens. Otherwise, I'm sure we'd see some huge lag on people with many (hundreds) large scripts loaded.
yes, of course this is the case :P you'll notice, for example, that changing a remote/alias file outside of mirc doesn't affect its operation until it's reloaded
