Drag-and-drop is evil.
You may ask me why this is. The answer is simple: you have to keep holding down your mouse button until the drag is finished. That is unacceptable. It is too easy to let go of the button and too difficult to maneuver the mouse while holding the mouse button down.
And thus, drag-and-drop (for anything but very short ranges is evil. As is copy-and-paste.
Copy-and-paste help alleviate some of the problems of drag-and-drop, but you have to epress Command-C (or Control-C on Windows), navigate Edit > Copy, or right-click (or control-click) and press copy.
