I know I won't get a real good answer for this one but I was just wondering of how much in the current set of 3GPP specs is no longer used at all anymore and, even more interesting, how many features and options specified over many years never made it to real networks!? With tons of features specified in each new release and only a few really used, I assume it should be a sizable percentage.
Why I care? Well, when reading the specs it's often not only difficult to interpret what is written but also if what you are just trying to figure out already is or will be used on day. Is this the price to pay for having one system to which (almost) everyone contributes to? What do you think?