This should have happened:
Wizarding World: WEREWOLVES ARE DEMONS! THERE’S NO WAY TO CONTROL THEM DURING THE FULL MOON!
Wizarding World: WE MUST SPEND DECADES TRYING TO COME UP WITH A POTION THAT WILL TAME THE SAVAGE BEASTS!
Wizarding World: UNTIL THEN, THEY MUST BE LOCKED UP!
Wizarding World: THERE’S NO OTHER POSSIBLE WAY!
James: Here, Remus, take this.
Peter: *Hands Remus a vial*
Remus: What is it?
Sirius: Shrinking Solution.
- Later -
James: See? He fits in the palm of my hand which means that I can easily hold onto him. As a bonus, his teeth are too small to break the skin.
Wizarding World: HOW INCREDIBLY SIMPLE!