No, and I've stated why.
The name says it all. I think this will be an easy method to use the same hotkey for both single casting, and switching on or off.
Things like "No and here's why..." never work. In fact, they make it so I don't even wanna vote for either...
The whole point of getting a hotkey to toggle autocast is to make it faster, holding it in for 2 seconds does not solve that problem. Maybe double-tapping the original hotkey or something to toggle it on/off