Hi,
In my experience, Thai always waived 10kg anyway. Sometimes the amount was 15 kg (in Y). I am a gold member and this was the norm i experienced for about 10. I have not really pushed the limits for the last 2 years as I have retired from my previous 'hobby' which required heavy traveling. Maybe now Thai will just be ultra strict and no longer waive any overweight luggage, except for hi so Thais.
Cheers!