@Nongnuch *******
I just cited that I understood they don't transfer the paper initial visa. "They don't xfer the initial paper visa. But they will copy stamps to a new passport." We aren't disagreeing here at all.
I've lived here the better part of a decade and I am married to a Thai and I speak, read and write Thai.
My name is now a Thai name, monk given, and my surname is my spouse's. Sorry if I seemed to be disagreeing with you in any way. I wasn't.
For the paper "initial visa" you will need to keep both passports around.