This is mainly for xc.
So most runners would do the long run on saturday, and the meets are usually on saturday as well. the thing is, wouldnt it be smart to switch the long runs on saturday with a faster workout? because (I dont know how true this could be) if the body is adjusted to running miles on saturday and all of a sudden it has to do a fast run, I think it would be harder for your body maybe. If your body is more adjusted to run a fast workout on saturday, it might not be so hard on the body when it gets to the meet, possibly.
Not that its effecting anybody really but I wonder if it lets off a few seconds by switching it up.
Not that many people have a choice since a lot of people are on a team and running together.