Drucker the prescient

You've heard about, um, what's his name?, Treacy maybe (looks like TREE-see but pronounced like Tracy)? with the three paths to biz success: operational efficiency, superior technology, customer intimacy?

I happened to see this just now in Drucker's Managing for Results (H&R 1964), p. 200:

General Motors, for instance, clearly prizes excellence in business development and business management (operational efficiency). At General Electric, on the other hand, people were for many years encouraged not to concern themselves much with business, but to excel as scientists or engineers (superior technology). IBM, until recently, stressed the ability to produce sales and customers, with the district sales manager the key man (customer intimacy - sort of)
(green italics mine).

When did Treacy's book come out (Discipline of Market Leaders, 1997?) -- and how many years earlier did Drucker point out practically the same thing - 30 or more? The guy was a genius.