Topic. These keys don't do anything by default. I more or less expected them to navigate the wheel in chunks (either large swathes or by letter of the alphabet or something similar). If it can't be made to work this way by default, then I suppose what I'm after here is a bit of script I can plug into the themes I'm using to force them to make it happen.
Navigation without something like this is pretty painful over USB2. Even after I took great pains to ensure that screenshots will load before videos, I'm still waiting too long for the visuals to stop chugging. And the search function is not a "seek" function.