Boiling Water 101

To salt, or not to salt, is only part of the question. How about when to salt boiling water?
Pasta cooking water needs to be salty, most Italian chefs will tell you that it should be as salty as the sea.  But, when do you add the salt, and does it matter?
Here's the science:  Put your pot of water on to boil, without adding salt. Cover it.  When it is nearly boiling, but not quite there, add the salt. This will cause the water to come to the boiling more rapidly. Adding salt at the beginning, while the water is cold, saps energy and actually makes the water take longer to boil. Adding salt at the near boil, creates energy, and the water boils quickly.
However, in all cases, it is always true: "A watch pot never boils."