[I'd go with what the maker says. He knows what works best with his knives, why try to second guess him?]
Yes and No. Short answer : because you are the user. It's your knife and you can shape it to your use. Putting a micro-bevel to the edge is not defiling a knife. However, if you are keen on keeping it original, don't touch it. Don't even use it, because field sharpening will slowly induce a slightly convexed edge... Anyway, these knives are users so the "integrity" of the original design is not exactly a point, I suppose.
I have many knives in several grinds : full V grind, V forged + sabre grind, scandi grind (which is a sabre grind, basically), hollow grind, sabre grind... Now, honestly, I sharpen / hone all of them regularly with a 20 ° angle on the belt sharpener. It produces a convex 20 ° angled micro bevel. The thinnest blades with steep sabre grind angles get more durable edges, while still being amazing slicers, and it works also for more robust blades. In the end, you are just micro-bevelling, so if the results don't please you can easily go back to the original scandi angle. To add : my Mora Classics work way better with the 20 ° micro bevel.