first, how do I check if this 10 LED reset did work? How can I revert this, if no difference?
UPDATE
omnia-eeprom set ddr_speed 1600K
does the reset, will come back if TOS 8 hbd branch will produce errors, which, from my point of view, were mainly related to APD7916NPD WiFi Card Firmware.
This setting goes to EEPROM so its independent of the system version. It’s stored on the chip memory similar where U-Boot lives. Also if higher clock works for you just leave it and there is no reason to downclock.
You may use get instead of set to get current value. Making 10 led reset is the same as using command I believe. It was added there if you cannot get console and your Omnia doesnt boot for compatibility only.