This is just so fkin stupid.
Can ANY authors please stop making excuses of background stories that make these kind of misunderstandings?
Surely, there isn't such as coincidence her tutor made her think a "stove flame" is stronger than what he showed to our MC.
A simple, "you are a lot stronger than me". Or "let me explain why this minotaur was so strong, aka the cow". Will fkin suffice. I've seen noone that made the mc character realize how strong he is through his friends showing how weak they are in comparison.
Not even my Mom is this stupid, and she cannot read the room at all.