HawkeyeMS
Ryder Cup Winner
But you have to define 'dedicated' - and as with any definition therein lie a can of worms. That said - you are going in a better direction with this suggestion.
However until things are sorted out the simplest and obvious way is simply to say no to any DMD in competitive golf. Nothing could be simpler.
Note that I'm specific about comps - I have no issues at all on their use in casual/friendly/practice golf.
It would be fairly easy to define a dedicated GPS I would have thought, anything that is designed for the sole purpose of providing yardages on golf courses and does nothing else (except maybe tell the time). it would also not be hard for the R&A to have an approved list as they do with drivers.