These two statements contradict each other. Yes, Sid Broadbent's Wellness Gauge is nominally calibrated for Wilson and MK spin rockers (as is the Blade Curvature Gauge from PBHE). The Wellness Gauge shows new Ultima blades as worn out (ready for discard); comparison of heel lifts also show new Ultima blades as comparable to worn Wilson and MK blades. These results are shown in the Paramount video on Lift Angles (https://www.paramountskates.com/videos). If you accept these results, that means the Ultima blades have flatter, not rounder, spin rockers than Wilson and MK blades. The Paramount video on Blade Profiles compares the spin rockers of the Wilson Gold Seal vs. the Ultima Supreme (at ~2:15 in the video), showing the flatter spin rocker on the Ultima."
The Ultima spin rocker region is shorter - so the Wellness Gauge is partly measuring the effect of the main rocker.
My interpretation of the problems I had adapting to the Ultima blades are as follows: The longer (less curved) main rocker, combined with the longer roll distance to the sweet spot (where the main rocker curvature changes to the spin rocker curvature) combine to mean that more strength is required to reach the sweet spot, and more angular speed is required of my ankle. Then, the shorter roll to the toe pick means that I had to abruptly counteract that ankle point motion, in a shorter distance and time, and that the shorter spin rocker meant that the change in force needed to keep rolling was much less - so I kept crashing against the toe pick when I only meant to dwell on the sweet spot. I believe that the resulting issues mean that you have to be a more skilled skater, with faster reflexes, to use the high end Ultima blades, than the high end MK and Wilson blades.
BTW, Matrix blades, as far as I know, have the same blade shapes as the lower line models with the same name. At least that is what the Jackson people I talked to thought, though they weren't sure. And now it may be different - my experience is based on an earlier Matrix line (the Matrix I line, with interchangeable blade runners), which is no longer in production, though I have enough runners (Dance, Surpreme [a much higher level freestyle runner than I should have tried to use], and Synchro, to last me the rest of my lifetime.
Interesting that you've found Ultima blades to have too round a spin rocker. Anecdotally, skaters, coaches, and tech's I've talked to have agreed that Ultima blades have flatter spin rockers than comparable Wilson and MK blades.
I think there could be that perception, because the spin rocker applies to a shorter distance along the blade, and the sweet spot is further forward. So I guess people think the are on the spin rocker when they are really still on the main rocker, because the sweet spot is so much further forward.
(However it has been quite some time since I measured the main and spin rockers of various blades, and the position of the spin rocker. It is possible I have somehow reversed something in my mind - but I don't think so.)
I think, but am not sure, that the toe pick on the Ultima Dance are longer and more aggressive than they were on the MK Dance, but I didn't actually measure that.
BTW, if money were no object, I would return to MK Dance, because I really loved them. Though I suppose it is possible I am now used to tUltima, and would need a similar adaption period to transition back.
Alas, after investing in the Matrix blade holders and all the runners I could find in my size (because they discontinued Matrix I just after I bought it - argh!), along with extra of the bolts that hold the Matrix I runners in place (which wore out quickly - a major defect of the original Matrix I design), I felt it would be too much of a waste to throw them out and buy MK Dance blades again.
It really annoys me that some kids adapt really fast to blade model changes, and I had so much trouble. I'm a lot older; maybe that explains it. Still - it isn't fair. I'm not alone. I have known a lot of adults who tried to switch blade models, and ended up going back to what they were already using, because it is harder for adults to adapt to new things.
But given Bill's contrarian results on the MK Pro spin rocker, it'll be interesting what his measurements show for the Ultima Protege. Of course, we still won't know what the manufacturing variation of various blades is.
BTW, Jackson implies
Protege are only intermediate level blades, designed for people starting to learn double jumps. That might conceivable mean it is less aggressive, and is easier to deal with than the Jackson Ultima Supreme, Dance and Synchro runners I tried - I just don't know.
BTW I simply haven't tried all types of blades. I generalize from a much smaller collection than Bill, and I'm not as good a skater.
For that matter, Mike C in his shop once showed me that at least one of the common high end freestyle blades (Gold Seal??) had changed a lot over the years. He showed me the toe pick position of old and new style blades, and they were much different. Of course that might make sense - over the years, there has been a strong emphasis in Freestyle on increasing the number of jump rotations, and even the standards by which they are judged have changed. In theory, evolving the shape was the right thing to do, though that may have confused some people.