"I think the advice not to post too much detail about what you have, where you live and when you are going to be out is sound. And possibly not what all of your anti-theft devices are either?"
Probably fair, but does come across a little like the theft version of 'you must wear a hi-viz jacket and helmet otherwise you're just asking to die'.
That said, I'd think posting anywhere that you've now got this lock and that lock, and bolts and an alarm would, surely, actually serve to put people off? 'Well I might as well go to that house cos it's just got the one lock...' Kind of like simply making your bike look like more hassle to steal than the one beside it.
I'd still be stunned if the neds in this case (given the nature of the theft before, and the break in yesterday), would have been as efficient to have trawled the internet, found CCE, read through threads looking for reports of stolen bikes, got my username, searched again to see if there were any threads about going out, found the thread about the cyclocross, assumed I'd be going myself, break in in broad daylight when any of the neighbours could be going about (and were, they were spotted fleeing by a couple). Rather than 'remember that garage we broke into because we saw the car with the bike carriers on it? Let's go back, there were another couple of bikes in there we could lift'.
The whole metadata thing is reasonably sound (though like steveo I've my doubts it's quite as widespread as that, certainly back when my other half was a fiscal the grand majority of thefts were entirely opportunistic); but the thing I've learned is, as mentioned above with the likes of having a complicated couple of locks on your bike, make it 'look' more difficult to break in, or that you have an alarm, or whatever, and they'll move on to an easier target (precisely because most of it is opportunistic).