If you have selected text, put the mouse anywhere over the selected text and press (and hold) the left button down. The mouse cursor will change and will have a little gray box attached to it.
Then move the mouse to where you want to move the selected text to. The caret shows where the selected text will be inserted. Release the left mouse button. The text will be moved to where the caret is. This is a fast equivalent of cut and paste. (But the moved text is not placed in the clipboard.)
If you start to drag text and change your mind, just release the button while the mouse is over any of the selected text. To drag to a place not on the screen, move the mouse past the edges of the window in the direction of the place where you want to insert the text.
You can Drag & Drop in Page, Regular, and Outline views. It is not implemented in Card view.