Although on the other hand you have to factor in the "General Purpose Technology", even within IT - some things are generally applicable and cause a great leap forward - things like Lotus 1-2-3, GUI/mouse, RDBMS, html/web, etc. (using older examples as the older a technological leap forward is, the more unambiguously you can identify it clearly as being a step change rather than an iterative improvement or of limited applicability). Of course in the same way all these are followed up by thousands of small iterative improvements and boring stuff to slowly creep utility forward while waiting for the next big leap.
