With the “Young Aesop” files coming to light. I have my thoughts on how he was as a student.
Like a lot of decent cops (aurors), he was a rapscallion as a child. He had all the experimental potions you could ask for. Fellow students would go to him to get the hook up of some fun ones.
As for the short cut reference. I figured he learned his lesson because he found out he was missing out on talking with witches he liked by racing ahead and using shortcuts to get to where he needed to go. He missed out on building some relationships because he was trying to get ahead. “Shortcuts lead to shortcomings.”
He did well not getting caught, especially as his skills solidified over time. He spent a lot of time acquiring ingredients he needed, and often found away into the restricted ingredient storerooms. His mischievous background as a child led him to be more observant as a teacher.
He sobered up over time, and focused in on his career. Maybe a classmate got hurt or he had a run in with a dark wizard. Something clicked in him to steer his life of seeking thrills from tomfoolery to helping others and tracking down dark wizardkind.
Those are my two cents on what I think a younger Sharp was like ¯\_(ツ)_/¯