Just a clarification: His article said to run a stone down the edges at a 45 degree angle. Not a Gumi stone. Nonetheless: I would never even think of running "a stone" down the edges at a 45 degree angle.
The last step is polishing the edges with an Arkansas stone at the set bevel on the base and side edges is what I do (that is how I have been taught by World Cup Level ski technicians) and, IMO, will take care of any deburring required.
I can understand your point about not touching the base bevel once it has been set. A lot of people agree with you. Still after you are done tuning the side edge you still have to run a stone down the base edge to take the burrs off the edge. Wether you do it free hand or with a guide is up to you.
My point was, just don't take anything you read in print as gospel. The best advised current methodology in anything, can change daily.
Absolutley true! I use a very hard grit stone, like an ultra hard gummi(it is not a gummi, to take the hanging burr off the base edge freehand)(thumb as a guide on the sidewall or side edge of ski) Probably one of the most crucial steps in tuning folks don't know about, and many shops won't take the little bit of time to do! I then make a very very light pass with a Toko finshing block 45 degrees to the the edge. Extremely lightly. Just makes the final edge ultra smooth. does not detune or take away any sharpness.
I also polish only the side edge as you say with an Arkansas or surgical stone ,as the final polish. all i can say is . Damn my skis ski good!