Of course this is impossible, the tool would give you a error message and switch to manual mode. But: If you download a hack from vB.org you will be asked to find
Code:
$DB_site->query("moo");
and you will not find it. You can't install the hack. And if you could (for example only one little change in the query) you simply have to do it via the manual mode - the one change or all changes, that would be your opinion...