Great blog post here on Universal Sports by Chloe Sutton:

Coach Rose is very smart and sneaky. He will give us a really hard and seemingly long set, but make it so that if we go really fast, we get out of some of it. One of those sets might be 30×100 on 1:30. He’ll tell us that we can go whatever speed we want on all 30. If we want to go 1:25’s he doesn’t care. BUT, if we go under a time that he gives us on any of them, then that particular 100 counts for 2. If we go 15 of the 100s under the time that Coach gives us, then we’re done. The great part about this set is that he’s giving us a choice and letting us feel like we’re getting out of something. Obviously, we all only want to do 15, so we’ll sprint 15x100s at a really fast time because of the extra motivation, and we feel like it wasn’t that bad because we didn’t have to do 30. My time to beat might be around a 1:04 on sets like these. That sneaky Coach Rose …