Do MK blades and Jackson blades use the same system of sizes?
AFAICT from a very limited set of examples, they do in terms of total length, and so do Wilson blades.
In addition, AFAICT they have correspondent hole positions, so that you can mount any of them using the same screw holes, and you will get approximately the same position for the sweet spot. Though that is complicated for Wilson blades, since many or all Wilson blades have two sweet spots up front. (By sweet spot, I mean a point at which the rocker radius changes.)
But:
The position of the toe pick and of the end of the tail, relative to those screw holes, varies with blade model. Perhaps with length too?
The positions and orientation of the oblong sliding holes relative to the other screw holes doesn't seem to be fixed for all blades, based on a couple examples I have looked at.
I've never checked whether hole position is the same for low level blades, such as those riveted onto cheap skates.
I've never checked out how hockey and speed skate hole positions and lengths work.
I think MK has made a very small number of co-planar mount blades for
Sid Broadbent's designs - which can't possibly mount exactly the same as most of their other blades.