I agree this is basically correct, but I adjust my saddles the old fashioned way--by experience and trial and error. No matter which method you choose, your pedals, shoes, and the saddle itself are factors too. Obviously, one way to get more familiar with what is right for your setup is to just try different heights, including those that you can tell are a little too high and a little too low.

While you are at it, remember it is called a saddle for a reason. It isn't the same thing as a seat. Your feet are supposed to contribute to supporting your weight, pretty much at all times. This means that your saddle needs to be low enough that your sit bones can float somewhat above the saddle while your knees are slightly flexed and your ankles are only slightly extended. I suspect that many riders, possibly even myself, have the saddle somewhat too high, because they want to sit on it too much.