There is an amazing example on that page which shows that the little tiny blip on the right side of the sensor (way, way, overexposed, and extreme ETTRing) actually has as much image detail as almost the entire image histogram. That's not what anyone should do. The point is just to show how much more data and details are being recorded for any part of the image that is on the right side of the histogram, compared to the left.
Actually, that page is an excellent example of why not to do ETTR.
Look at the three adjusted histograms. Notice that tall spike on the right on the rightmost histogram? See how it's the only part of the histogram significantly different from the other two? And how it goes all the way to the top?
Even though that spike isn't all the way at the right edge, it still represents saturated, blown-out pixels. All that's happened is that ACR has uniformly reduced the blown pixels to a still-uniform value less than maximum.
Sure, the shadows are cleaner. But I bet a 100% crop of that ``Prairie'' sign would show much more detail in the properly-exposed version than the overexposed one. Were that a wedding dress, Mr. Schewe's smartypants exposure hijinks would just have made the mother of the bride very angry indeed. Even though his histogram showed a "good ETTR" exposure.
And have a look at the waterfall, too. Sure, he was able to recover a good amount of tonality, but the colors are posterized to a ridiculous extent. That exact same sort of posterization is going on in all the other overexposed highlights, with the degree of posterization proportional to the amount of overexposure.
In other words, using ETTR means all your specular highlights will be either devoid of color or have that same sort of severe posterization. Now, granted, the definition of specular highlights is that they get blown...but they'll be much bigger in area and the transition from colorful to blown will be much more abrupt and less colorful. You're basically taking a sledgehammer to your specular highlights, when they really should (in my opinion) remain light and delicate.
By all means, if you like the ETTR look, especially if you're shooting sleeping black cats at the bottom of a coal mine, go for it. But, when that cat wakes up and you want to capture the glint of the candlelight in her eye...use ETTR if you want the glint to be a hard-edged white outline, and expose properly if you want it to look like a candle flame.