I never said that the 9.3 Mauser was not born from the 7 and 8 Mauser, what i said was that I agreed JoeBob in that it was a separate development. What I meant by that is Otto Bock's 9.3x62 case isn't a exactly a lengthened 8x57 case with a larger bore. The 8x57 has a base diameter of .470" and the 9.3x62 has a base diameter of .476". This is similar to William Brennke's 7x64, technically it's not a 7mm longer 7x57 because the base diameter is .467 vs the .470 for the 7x57. In the same vein, the 6.5x55 is a separate development because of it's 0.480 base diameter. I will agree that this is also nuanced minutiae.
What I know of the 30-01 is that it was an experimental cartridge with a case length of 2.554"~2.564" developed for testing but not actually adopted. Frankfort Arsenal loaded up 10,000 rounds for development and in 1903 it was shortened to 2.54" and adopted as the 30-03. As you said "nuanced minutiae".
What I find interesting is the timeline on P88 and Paul Mauser's 7.65 x 53 and the advent of Paul Vieille invention of smokeless powder just a couple of years before.
Was 7.65 x 53 the Beta of the day... and P88 the VHS?
VHS prevailing? P88 prevailing? Lower chamber pressure?
German Rifle testing commision would have liked that with the "new" smokeless powder "concept".
As for Bock and his 9,3 x 62 desire and design. I see the the delta between 57 and 63 serving three functions.
Overreaming and reboring existing surplus weapons...
Adding case length to balance safe pressures
Max COL for existing actions.
9,3 x 62m was 100% invented as a "Working Mans gun" for Africa.
Regardless of how it occurred, I love the caliber.
FYI, you knowledge is impressive.