Well I don't think a full fledged secondary bevel is the way to go. What I have been doing is using the 30 degree Sharpmaker and putting a very thin micro bevel on them after I have worked some of the "newness" off the factory edge. Just a few dozen passes with the Sharpmaker on each of the 4 grits or whatever is perfect. 30, not 40. I always finish an edge on a strop loaded with green compound especially with the sharpmaker which seems to produce more of burr than diamond plates. The Mora scandi edge must be about 20 or 25 inclusive so while very sharp and bites great, can be a little delicate for hacking tough material, field dressing, butchering. The factory edge is ideal for wood carving which, truth be told, I do very little of.
After a few sharpenings the bevel starts to get too wide to be considered micro, and then I lay the big wide scandi bevel flat on a diamond plate and basically "re-scandi" the thing. I used to always lay it flat but I am finding a micro bevel is quick, does not compromise the wicked cutting ability of the scandi, improves durability, and again does not compromise the ability to "re-scandify" the thing after a few interim sharpenings.
I would strongly recommend against a more conventional secondary bevel on any scandi knife.