Holy cow, I wrote a book!
Commenter Phil Quirk notes via the suggestion box,
"MoveWindow is just a weird function.
I guess it's easier to call than SetWindowPos,
but that's the only thing it seems to have going for it."
Yup, that's about right.
The MoveWindow function doesn't really do anything
you couldn't already do yourself with SetWindowPos.
It's just a convenience function.
And it you look at it pretty closely, it's really not that big
of a convenience either, saving you one parameter
and replacing the flag SWP_NOREDRAW with a boolean
It shouldn't take too much imagination to figure out how
this situation came about.
It's the same reason why you have both
CreateWindow and CreateWindowEx.