These are music experts?
"the Rolling Stones – burst onto the US charts with a rocky sound that swept away popular music's jazz and blues chords."
Yeh, the Rolling Stones were really well known for their dislike of blues, and sure swept away its' chord structures with their avant-garde atonal serialism......
'The second greet stylistic revolution came in 1983 when electronic bands using new instruments (synthesisers, samplers and drum machines) burst on the scene.'
Is that "new as in just invented" or "new as in just bought it from the shops"? Anyone who thinks that these things were invented in the early eighties has no clue whatsoever.
'The most recent upheaval (and for the analysts at least, the greatest) came in 1991 when rap and hip-hop (which make little use of harmony, emphasising speech sounds and rhythm instead) hit the mainstream.'
So Grandmaster Flash, etc, didn't have worldwide hit records in the early 80s?
What's the conclusion to their research? That a new type of electronic dance music called "house music" is about to become popular?