As far as I understand it - El Reg don't do keyword scanning. Certainly I occasionally deploy a swearword or two. It's currently 16:42 and I'm hitting post - so let's fucking test the bastards...
Most Andrew Orlowski articles go on pre-mod. Which means all comments get put in the queue until they get round to it. That's going to be a long time at weekends. When they're mostly in the pub. Even if they've got a Weekend Register, they're probably still publishing the articles from the pub...
They're also likely to put anything legal on pre-mod. If they bother to open comments at all.
However, having been a moderator on the forums of an online game with a million users, I'd like to make a couple of observations. For context El Reg I think has 5-10m readers. We had about 150 volunteer mods to keep the forums in order. Admittedly that was because of the game being global with 30-40 languages. But moderation is expensive and time-consuming. The Register have said they don't have mods, but their subbies and whichever hacks have a minute spare go on the forums to try to keep order. That means the pre-moderation queues will also be longer.
Secondly that also means you're not likely to get an explanation as to why your post was nuked. They'll just go on gut feeling as to allow/kill, and move on to the next thing.
Thirdly this is a pretty damned lenient forum. You can get away with swearing and quite a bit of off-topicness. As well as general silliness and a bit of good-natured abuse.
They've got their house-rules at the top of the comment box. Have a read of them. I don't know what your offending post said, but if you were having a good old go at the hack what wrote an article, what did you expect? It's their website, and their forums. Try arguing the points, and not the man. Start calling authors shils or idiots, and you're liable to get modded. If it's not that, were you losing it a bit with other commentards? What do you mean by "the odd angry post"?
My advice from my moderating days was, go away and read another piece after you've written that angry post. Then come back after a minute or two and re-read it before hitting submit. Or edit/delete if it's OTT. You have to work at it to get modded on here.