Great story Jim.? Deserves a thread of its own, actually.
Not that I've ever tried it (or perhaps I have but didn't know it), but I'm amazed when I hear that a minute change such as 1 degree more or less edge bevel can make such a huge difference.? I skied my Speeds right from the factory with whatever tune they put on (0.5/3, I think) for about 2 days before I filed them at 1/2.? Can't say I really noticed much difference, other than I found the edge grip with my tune to be better.? They were definitely sharper after I got done with them, but even with the factory tune I didn't feel any of the grabbing that Jim describes.? But then, I'm not nearly as experienced as you guys, so probably wasn't skiing in a way that would make me notice it.
I had never been able to feel a difference before either, and had similar thoughts wondering how other can people notice a 1 degree side bevel difference, or a 1/2 degree base bevel.
Grabbing may be a bad description. It was pretty cold and had been windy, so there were places where the surface was very hard and scraped off, the kind of place where you mostly slide and scrape across it. As I would ski across it now the skis would catch and edge (stop sliding slideways) and then release (start sliding again). At the time it was a balance challenge, but as I thought about it I believe that "just a bit more tipping" and I could have held that edge and skied across these very ungrippable sections. The change in feel was very noticeable.
On softer snow, I really didn't notice much difference.
I have also been working on a drill that Gary shared where you tip your "non-stance" foot while skiing fairly slow, to feel the effect of that ski tipping as it pulls you into a turn. This is a Clendenin drill, not Harb, and I could definitely feel a lot more from the ski with the new tune (and this is at slow speeds and very low angles).