How many times can I enter Thailand with a multiple entry DTV?

How many multiple entries in a multiple entry? Ok I know its a stupid question but one that is in the back of my head. My fiance' (a Thai citizen) and I are taking full advantage of the multiple entry of my DTV, since I originally arrived I've left Thailand six times, sometimes for a day or two. Comeing back is going through immigration again, new TM30 (which I do myeslf at her house) new stamp, extension in the six months in my passport. I'll admit I'm a worrier. But it only takes one inquisitive immigration officer, one note in the computer, one denied entry, one major suspicion and it could all be over. They can cancel your DTV at will. Now my fiance' says not to worry, she's a corporate banker and some of her colleages are leaving the country weekly sometimes more. But they're Thai citizens its a compltely different situaiton. So am I worrying for nothing? I've never once been questioned, just stamped through.