Using text-indent: -1000px is a terrible hack anyway. Some hacks are necessary but when you're moving elements off the page to achieve an effect, you're definitely doing it wrong.
patio11 clearly said in his blog post that CSS wasn't his bailiwick. Instead of simply saying, "You did it wrong!", you might say:
Here's a link to some popular CSS image replacement techniques: http://css-tricks.com/css-image-replacement/
It's also worth pointing out that, in that article, patio11's text-indent hack is cited as probably the most-commonly-used method.
If you've been at it for a few (and I do mean "a few") years, building sites that work in all major browsers (FF, IE 6 - 8, well, alright, Safari) turns out to be not the most difficult thing in the world.
Also to expand on it a little more, I use(ed) this trick a lot, and I've never had the image shifted off the page. I'd be interested to see the HTML that actually broke.
I didn't mean to comment directly to the author but make a general statement of the current state of the art in CSS: to achieve an effect use the craziest hacks one can find. As you said, patio probably just found that code on the web and used it.