It's unclear to me what you want it to do.
It shows help when you hover over either of the buttons. Is that
what you want or something else?
I don't know if you want something to happen when you hover,
click, or something else.
If there really is a performance problem, you can improve it a bit
by creating variables with your jQuery selectors instead of writing
them inline each time. And you could use a data- attribute and use
jQuery .data() to
retrieve instead of using a made-up attribute. (It is more efficient.)
Those may just be nuances. But when you are doing something on
mousemove, you
should optimize the code as much as possible.
But I haven't seen a flicker yet. ... I take it back - the
original jsFiddle does not flicker. The second one above flickers
badly. Jake's doesn't flicker, but may or may not do what you want.