It's unconventional, but 9.3x less memory can be seen in some sense as 1/9.3=10.7 percent as much memory. Not defending it, just trying to interpret :P
Actually, it's 10.3x less memory (they've subtracted 1), so it's using 9.7% as much memory as the previous release. I would have said that 90.3% less than before, but maybe that's just me
You can't have 9.3x less memory, either. You can have (1/9.3)x as much memory, or they could just say 10% as much or 90% less.
I agree that it is technically unsound, but the meaning of "Nx less of something" is still relatively unambiguous when N>1.
Yes, it’s stupid (ambiguous, imprecise) terminology, but pretty common usage when describing computer benchmark results.