Not at all.
If you just MUST, then rather than rounding the edge, ease up the base angle a bit, starting just forward of where the edge, when tipped, will begin biting into the snow, say taking a 1° base angle to 1.25°. (Not suggesting you do those angles, just trying to make my meaning clearer.) You're trying to prevent a "premature edge bite" if hard snow is uneven.
This detuning crap is why I do my own skis. Locally, some stores will go as far back as a foot! If I take my skis in, I tell them no detuning, no deburring, etc., I will do it myself because I can ease into it if the ski feels hooky. Detuning is left over from the days of long, straight skis. But I want the full edge for if I'm on steep ice. I've taken skis back in a rage over this detuning thing.
Oh yeah, the "gummi" will definitely round the edge. Get a stone in a base guide.
