[Usability] Auto-raise windows while drag-drop engaged?

[Dave Ahlswede <mightyquinn charter net>]

I'm just wondering, has it ever been considered to have
unfocused/obscured windows pop up to the front when you hover over them
while dragging something? Additionally, the window might be lowered to
its previous position when the mouse leaves it.

I vaguely recall something similar being discussed in relation to the
window list panel applet, but it might be better to also have it happen
with the windows themselves.