There is another factor that we haven't considered, that matters a lot to some people. The material in high end MK and Wilson blades is beautifully reflective, as is the excellent engraving on them. None of the stainless blades I have seen matched their reflective surface or artistic engraving. Also the brazed joints of high end MK and Wilson blades (though not the higher end Revolution blades...) are simple and clean, whereas Ultima and Paramount blades have a more complex looking joint and shape that I suppose detracts from their appearance, for some people. Blade beauty isn't important to ME, but figure skating is a visual art form.
OTOH, Ultima and Paramount have both produced color tinted blades, which some people love, for reasons having nothing to do with strength or wear.
And of course, if non-stainless blades are allowed to rust, that appearance advantage completely goes away.
I wonder if the amount of friction with the ice could be different for different steels, or titanium. There ARE some published results which claim that lubricated titanium has a significantly lower coefficient of sliding friction with itself than lubricated steel does sliding against steel, so titanium blades MIGHT glide significantly better on ice. But one would actually have to measure the friction created by various sharpened steel and titanium figure skating blades to guess with better certainty, and perhaps the comparison would vary by ice conditions and sharpening technique.
This is wandering way off topic.
Paramount's site has changed since I cited it, or maybe the way cited it arrived at a different page. E.g., the page I found mentioned that steel wore on ice by coming off as "molecules".
It is possible there are electrochemical factors to figure skating blade lifetime on ice. E.g., car manufacturers and others use "sacrificial anodes" to slow down rust and corrosion, because there are major electrochemical factors to each. I have no idea whether any of these blades have something similar. Incidentally, someone who visited the MK/JW factory told me that they tempered and hardened their blades at least partly by electrochemical means, over a period of days, not just by the thermal and mechanical means. I don't know the details, or if it matters.
>As for my personal experience, I carefully dry and store my boots and blades, regardless of the material, between sessions.
But if you don't also oil or grease the blades each time, ambient moisture might still affect the edges. I was taught long, long ago that many steel tools should be kept oiled.
If you don't, that might have biased your results.
My own tests weren't completely definitive either, because I usually only oiled the blades when I wasn't going to skate again for a few days. And I've never done high level jumps, or high level skating, either. I stopped testing when initial, non-exhaustive results showed that stainless steel Ultima Matrix I Dance edges stayed very sharp MUCH longer than non-stainless steel MK Dance edges - FOR ME, under the conditions I used and hand sharpened them. That's a potentially biased sample.
So I'm not absolutely certain a very conscientious skater couldn't treat high carbon blades well enough to do about as well.
The tests I did personally convinced me it isn't true. Your tests tend to confirm my results, but are also a potentially biased sample.
Either MK or JW once said online that their blades were made of a high grade
spring steel, which suggests that impacts were a major component of their decision to use what they use, and it's possible that it is important, even though figure skating blade breakages are not so very common. Though that decision was made long ago.
One thing I was told, though this may be out of date, is that metallurgists sometimes spend years getting production details completely right on specific products. For example, when MK and JW first combined and moved to a new facility, I was told by a skate tech that some their metallurgists quit, and that there was a period of about a year when their blade edges were not nearly as hard as they had been, and that his customers complained that those blades needed more frequent sharpening. So maybe for MK and JW to switch to a stainless steel allow, such as 440C, they might have another period of time when their blades weren't as good.
In addition, because some of their current customers believe non-stainless steels are better, they might lose some of them. Faith is just as important as reality in sales.
Do you know anything about hardened titanium alloys?
There are several titanium figure skating blades being made right now.
Possibly because in other applications it corrodes less, possibly because it weighs less for a given strength (which might well be quite important), or possibly because people "think" titanium must be better because it is more expensive. And for all I know, it might be much better - I've never had or tested them.
I did look into the cost of titanium, high carbon steel, and high carbon stainless steel, and they are all less than $1 / blade pair, so I don't think material cost is a the prime determinant - though I don't know how the other costs and times that go into making figure skating blades of each material compare.
BTW, there are published claims that titanium wears much more, and is softer, than steel, though I don't know if that is true of the alloys used in figure skating blades.
Part of the problem for me is that I can find published articles online on such things, but the most informative articles I have found are published by or funded by the companies that sell the materials or products made of them. I don't know how much that biases the claims. And none of the particularly informative ones I found relate clearly to figure skating blades used on ice.
Let alone other skating materials, like "synthetic ices". Because those synthetic ices wear done blades so much faster, material differences might matter a lot to people who skate on them, like some show skaters.