Things changed. Is detailed analysis of individual stocks necessary?

Just before he died, Graham was asked whether detailed analysis of individual stocks - a tactic he became famous for - remained a strategy he favoured.  He answered:

"In general, no.  I am no longer an advocate of elaborate techniques of security analysis in order to find superior value opportunities.  This was a rewarding activity, say, 40 years ago, when our textbook was first published.  But the situation has changed a great deal since then."

What changed was:   Competition grew as opportunities became well known; technology made information more accessible; and industries changed as the economy shifted from industrial to technology sectors, which have different business cycles and capital uses.

Things changed.