If you look at the mobo, it's got several locations with pins just sticking up doing nothing. Many look kinda like the pins the fans plug into. There are some of those ports you actually have a need for, such as the USB2 header, cmos reset jumper, fan headers, audio header etc. Most are asus specific for test probes when a board gets rma'd and you will never use them.
The cmos reset jumper for instance, normally comes 1 of 2 ways. It'll either be 2 pins or 3 and either is just pins or has a small square plastic covered shorting plug on pins 1-2. To reset the cmos, you'd temporarily move that shorting block to pins 2-3 then back to 1-2 for normal operation.
Whomever wrote he'd found the usbpwr block, has found another such header, one that seems to operate power to the usb ports at pc off state. There's a shorting block on pins 2-3, he moved that block to pins 1-2, which seems to be a cure for usb ports retaining power after shutdown. So no more keyboard or mouse power when pc is off.
What he hasn't said is what else that affects. Does it affect his boot up process, where there's no power until windows loads, which will prevent bios access or does it control sleep cycles where the keyboard or mouse will not wake up the pc from sleep etc, forcing a reboot.
If you do follow his advice on pin settings, be aware it can have unintended consequences.