I am looking in to how late bindings occur with variants (such as TWordApplication) and why they can't be applied to objects, or can they?

I am looking in to how late bindings occur with variants (such as TWordApplication) and why they can't be applied to objects, or can they?
From what I have came up with (right or wrong) is that there is some compiler magic involved and it is around the IDispatch interface. So why can't an object, that implements the IDispatch interface, have late binding calls? Is it because of the compiler magic that happens? I don't mind reading, so if there are any links you have got, I wouldn't mind reading them :-D