Having read about it I decided to do a small test myself and came to interesting conclusions.

It seems to me that in low light and conditions requiring higher ISO, there's no point in ETTR since you'll have lower shutter speed which in normal exposure you can compensate by having a stop lower ISO.

But still, this is a shadow crop from both at ISO1600, you can see ETTR method having significantly lower noise, but still - not too practical in real use.



However, for a lanscape shot in which you're going to use low ISO anyway (or native) there seems to be a significant advantage because you can sharpen without it affecting noise and ultimately get cleaner, smoother looking image which is just as sharp:

These 2 shots were opened in ACR-a with following settings: (S:55, R:0.7, D:26, M:20) at ISO200 without any NR.

First one is "as is" while the other one is ETTR +1 shifted to -1 in ACR.

Second sample definitely has better quality and much less noise all around.