the m2m cutter will make the same changes while on the cutting table.
in r.t.w. they usually just add more shoulder pads to fill the space. its the most economical way to do it.
the second diagram shows that there is one expensive alteration that can be done.
the sleeve must be removed. the collar pulled from the neck hole. then the shoulder seam re sewn as a sloping one.
the sleeve cap is cut to fit the new armhole, and that cutting depends on the tailors expertness, and a lot of luck. see the arrow.
a bonus in this, is that the bottom of the armhole comes up. if the amount taken at the top of the armhole is one inch then
the armhole is one inch closer to a high armhole. dont get excited, because one inch is usually not enough to make it a true
high armhole. thats because the rtw armholes are so very deep.