Strangely changing the mouse double click speed setting to max seems to make MC respond a bit quicker to the clicks on the "Move Up" or "Move Down" button, but you certainly cannot single-click these buttons as fast as the double-click setting allows.
That is exactly what I was trying to convey in my reply: by maximizing your mouses double-click speed setting, you can now single click more rapidly
and it will not be interpreted as a double-click, and thus MC can respond faster to each separate single click event.
In your video, when you were rapidly clicking in 2 different spots, those are interpreted as separate single-click events. When you click twice rapidly in a single spot however, MC (or any program for that matter) will interpret that as a double-click event (depending on your mouses double-click speed setting), and thus ignore it and not take any action (for your specific example).
To me, there is still something not quite right with the behaviour of these buttons. Even with the mouse double-click setting on MAX, I can only single-click the up or down buttons approx. every half second and have it respond...
the thing that is "not quite right" is the
other item I detailed in my reply - MC does not initiate the expected action on the mouse button
down-click, but waits for the button to be released first (mouse-up). This is very easy to check, simply click and hold the button and notice that nothing happens until you release the button.
Sometimes this behavior is a good thing, other times it can be annoying, but in most cases the difference between them goes unnoticed. That said, Matt/JRiver could modify various portions of the code that would benefit from initiating actions on the down-click instead of up-click (your specific example of moving items up and down in a list would be a good candidate).
I do agree though, there are various MC elements that seem to have an extra "beat" between mouse-click and action - not everywhere by any means, but in a few places it is consistently one tick too slow.
