What kind of "an enthusiast and self-confessed keyboard snob" treats n-key rollover as trivially as this: "ABS also claims the M1 can register six simultaneous key presses, but I haven't been able to reproduce that consistently. Holding down "QWEASD" or "ASDFG" produces no output, although the device is happy enough with "ASDJKL." (For what it's worth, the Das Keyboard cheerfully registered as many keys as my fingers could hold down on the home row.) If you're wondering about those bad Newegg reviews where users say the M1 doesn't let them hit simple key combinations like "CTRL-S," I haven't run into any such problems. In my experience, the M1's key rollover is more or less average."? 'Average' is 3-key rollover and and the failure of ASDFG doesn't just run astray from what we know about USB but also falls short of ABS's actual marketing.
If you plug geekhack and yet don't know about the limiting USB HID spec, I would say that's rather jeopradizing of the integrity of the whole article.