I got a cab some months ago with a young driver, he'd play a playlist, scrub the song to jump around the 01:00 mark, listen to 30-45s of the chorus, scrub again to find the 2nd chorus, and skip the song afterwards.
It's like the exact opposite of the ol' skool DJs skipping all of the choruses to play just the breaks. The guys playing the breaks started a huge movement. Maybe this driver is ahead of the curve and might be making the next big thing in music?? (no, i don't really believe that)
DJs playing records and DJs buying records are two different things. When you're looking for records, it's quick listens and gut decisions to keep or dump. The labor of love is only applied to stuff that makes the keep pile.
What's you point? You think DJs don't have large collections of vinyl? Tell that to the 15 crates sitting in my room. You think that doing needle drops looking for breaks is any different than doing needle drops for the chorus? You can look at the grooves in the record and read the track. You can easily see where the breaks are, and you can see where the chorus would be. So I'm at a total loss on what you think is different