So you're basically suggesting ruining the multi-user environment that mirc (or the user himself) has correctly set up and going back to the Windows 95 days... not to mention that writing to Program Files (most likely location of mirc.exe) is not even allowed on regular user accounts.
Multi-user issues have been discussed to death here, I hoped you'd be at least aware that there are such issues and would accompany your suggestion with some sort of disclaimer.
