Teaching job with just a TEFL qualification ?

From what I understand, you need a bachelors degree in something, anything, in order to get a teaching visa. Maybe you can get a work visa, but not a teaching visa...?

What kind of research are you doing? Where have you heard that you don't need a BA in order to teach English in Thailand?

Here are a couple of well-respected sites for TESOL teachers. Do they ever say anywhere that?
http://www.ajarn.com/http://www.eslcafe.com/jobs/

One point; the employers who do not require a BA, may be employers you don't want to work for.

The answer to your question would be "yes", you can teach anywhere and anytime if you have an inborn gift for teaching and giving instruction. But with regard to qualification to teach English in the eyes of the employer, please allow me to provide a little insight from my life's experience, and then you can like it or lump it.  Besides being a professional musician/producer with 55 years experience, I am also a professional TESL/TEFL instructor/teacher-trainer with 26 years experience. I can only say that people with a BA who haven't had college level TESL training and a basic background in applied linguistics, can't teach their way out of a wet paper bag. Employers who are hiring based on only a BA, are very uninformed in the art of true language teaching and the nature of first and second language acquisition. That being said, the only guarantee that an employer has is that the wanna be TESL/TEFL instructor at least have a post secondary education in the English language environment -- Maybe the new employee with a BA will at least be popular with the learners in other ways and go on trips and just talk English, but that employee still can't give valid instruction in second language acquisition. I almost finished my degree (linguistics, writing & rhetoric, cinema) but I didn't, so I can't get a standardized teaching job overseas. I have tenure where I teach in the west because of the nature and international recognition of my certification -- i.e. I am a specialist and trainer in TESL/TEFL. So, to sum up, without a degree, you had better know how to keep ahead of your learners and their texts and other materials by acquiring proper education in the art of instructing in language acquisition and basic linguistics i.e. the ability to teach grammar rules around a theme, the ability to help with pronunciation errors through analysis of the contrast between the first language and the target language, the ability to conduct a needs-analysis and a language proficiency analysis, etc. etc. . . . or get a BA in anything and get your experience in teaching English by flying by the seat of your pants. Taking any internationally recognized course in TESL/TEFL/TESOL can't hurt your chances. You would be better qualified than a BA grad who got their TESOL out of a Cracker Jack box.  Rock on and Good luck.   dcb