On paper yes one would presume that however I see Thailand has tax double tax treaties with many many many countries and as they are after money money money they will find a way around it or they will try At the end of the day it's about money in the pocket
and added to that, often there ARE NO CLEAR RULES.... was on an EDU visa.. and the big mouth immi farang hpe told me strictly I would need leave TH and come back to start the Retired visa... total BS .... so, dont beleive anything!!! good luck
well said, however.. have to put yourself into the farang mind... they feel safer in their country and like to preorganise... (espacially germans) and most dont know about the o visa until its too late..