Yeah, you are right. Didn't think of that.
You could just make an external link and use the Itemid of that link itself.
But that would mean you have no control over the settings (amount of intros/links/etc).
Another option - but kinda hacky - is to make your link as a normal section blog link. Enter the settings you want.
And then change the url in the database to:
index.php?option=com_content&view=section&layout=blog
But that will mean you can't save changes via the normal administrator. It will ask you to define a section when you want to save it.
So if you want to change settings after-wards, you would have to select a section and remove the id= from the link in the database again.
Anyway, if you don't plan to muck about with the menu often, that does work
