"One of my favorite coinages, or twists, which I think I only ever used on  my blog is 'common groove'  -  basically, I have this polemic that the best black music, whether it's funk or disco, tends to be the most commercially successful stuff. The cream rises. 

"Nowadays, because of all these obscurantist reissue labels, you have a generation of hipsters who have listened to all this objectively second or third division disco, funk, etc  - but have never actually listened to Rose Royce or Stevie Wonder or Chic or whoever - the stuff that got into the charts and that masses of people bought and listened to.  

"All that stuff is common groove because there's loads of vinyl copies lingering in the world, going dirt cheap - and full of wonderful music. You could probably pick up 7 albums worth of it for the price of one of these stupid obscurer-than-thou deluxe vinyl reissues. 

"It relates to the Retromania chapter on Northern Soul. That was the original 'rare groove,'  although they didn't use that term, they talked about rare soul. The Northern Soulies had a whole thing where they wouldn't play Motown because it was 'commercial' - all that meant though was that it was so indisputably good that ordinary people liked it and bought it!  The 'rare soul' was just as commercial in intent, it's just that it wasn't good enough to be commercially successful.

"Same applies to 'rare groove'. It's basically the failed stuff."