If you have a Naga or similar,
Make a macro like:
X = Your keybind for DnDCode:"Press X button" "Press left click on mouse"
If you have a Naga or similar,
Make a macro like:
X = Your keybind for DnDCode:"Press X button" "Press left click on mouse"
...and if your mouse is in the upper right corner of the screen, DnD will go there. You still need to position your mouse, you're just saving a button press. Thing is, it's difficult to position your mouse in the middle of a fight without aid, that's what the big green target reticule is for.
How exactly is hitting the same button twice faster than hitting the spell and clicking, considering you have two hands? You can double tap quickly but I don't see how it would be faster than hitting the button and clicking almost immediately since you know, different hands and all. I mean, you still have to aim the spell with your mouse anyway. Might be a point if I had to hit the button and then click the mouse with the same hand or something, but they can be done almost simultaneously.