matchboxbananasynergy
Begging your pardon; I just uninstalled keysh, and whilst playing media, tried (screen-off) a long press of the volume keys. Only the first press seemed to register as altering the volume by an increment. Holding the button did not continue to "push" the volume up or down, as it would do if the screen were on.
My conclusion is that, at least on my device, there is no trade-off in volume-key functionality when using this workaround.
Yeeehaw! :D