Responding here because it directly pertains to this thread.
...the half life of information in computing was roughly 4 years. I don't know of any reason to believe that has gotten shorter, rather the contrary.
Don't you mean longer?
Since the rate of advancement and change in computer science is accelerating at an increasing rate, the half life of information in the field is getting shorter.
As I said, there's no reason to believe that it has gotten longer.
