I just came back thru Bangkok from US on a DTV. Hit the Priority line because I fly business class. Right thru with no issues. Another guy 2 lines over was being asked all kinds of questions. After about 5 minutes they stamped him in.
I saw him at the luggage carousel and asked him about his interaction. Seems he just got his DTV for Mual Thai but also has a ton of prior entries over the years with a handful of exanswered.
I assume that was the main issue. I have always come in on a METV or was in and out in a few weeks without an extension. I also assume he is going to be a frequent question answerer.
This guy was a little loud and the "I have a visa you have to let me in" was not a good way to handle it. If that person is on here...Good luck in the future.