This. I use to be a champion of all nighters and cramming, until I got serious with my time management and maintained a healthy sleeping pattern.

1st-3rd year with all nighters -> average low 80s average. 4th year with maybe 1-2 all nighters -> low 90s average.

Of course other factors contribute and as she mentions in the article by your final year you know how to get high marks, but I see the error of my ways not following good sleeping patterns for the earlier years of my undergrad, bloody youthful exuberance!