If you could see exactly who was in queue, their MMR, and who they are grouped with, and who is solo and their MMRs…
It would all become crystal clear to you. You would see what the matcher is dealing with and how it “solves the problem” to create the matches.
If matchmaking was turned on, you would see the top teams waiting because no matter who they were lined up against, the quality of the match would be below the threshold and that match would be rejected. This would go on for a very long time as the lower MMR solo people played against each other in acceptable matches.
Scrapper: “Frank from Research”