If the scene is of relatively low dynamic range, consisting mainly of midtones, there's no great need to expose to the right. Correct exposure for the mid tones will suffice. If the DR of the scene is wide, as many landscape shots are which include sky or sunlit areas, then exposing to the right is pretty essential for noise-free shadow detail.
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Actually, you have it backwards...in the case of a scene that DOES fit in the dynamic range of a sensor, you are GOING to get far smoother captures by increasing the exposure and placing more of the scene in the lighter tones-as long as you don't clip textural highlight detail.
In the case of a scene that exceedes the dynamic range of the sensor, your only choice is to decide, your self, what part of the scene is the most important and expose as best you can knowing the bright specular will clip. The ONLY way around this is to either shoot multiple exposures to assemble after the fact or do a dual process from raw to regain as much highlight detail as possible and blend the highlights into a normally processed image.
The other factor Rags seems to ignore is that sensors wiill indeed vary camera to camera-although a single camera will itself be pretty constistant.
When you set the ISO to 100, it's a nominal setting. Your actual sensor sensitivity might be 80, or 120. This can indeed impact the way your exposures will be biased when shooting. Using an exposure compensation will help nail exposures better based upon the REAL ISO of your camera, not the nominal ISO. Once to nail that, the next step is to learn the exact dynamic range of YOUR sensor. Is it 6, 7, 8 REAL stops? Depending on your acceptance of noise, one can make an argument that many DSLR are at or near 8 stops, maybe a bit more-particularly when you examine just how much data is there nclumped, not clipped at the highlights if you can get to it.
Camera Raw does a really remarkable extraction of highlight detail, why? Aside from the fact that Camera Raw DOESN'T quit when the first channel is clipped, the fact is there's an enourmous amount of detail in those extreme highlights. It's there if you know how to use it.
Which, if you approach exposure based upon metering for the mid-tones and letting highlights and shadows fall will pretty much make sure that you loose that advantage of controlling the usefulness of your dynamic range and your bits.
Back when sensors first came out, there was a serious problem called blooming that would have photosites in a sensor woth extreme spectrals bleed accross to other photosites and creally blow out. In that period a photographer HAD to "under expose" digital to keep from having speculars blow accross large portions of the sensor. Those times are effectively ended with today's sensors which simply do not bloom like the older ones did.
The problem really boils down to one of convention...digital sensors are NOT like film. They do not react the way chrome nor neg film reacts to light. Therefore you really can't use old film exposure techniques...the aim is to get as much data captured as far up the scale as you can while still preserving usable textural highlight detail. This is NOT "over exposing" it's "proper exposing"-for a digital sensor.