I agree that letting problem grow isnt always the best solution.
I also agree that resolving the problem early on is usually a safer strategy, however taking risks is sometimes worth it, especially if you are convinced that the situation wont get out your of hands. (Thats what vilains usually do, but they get wrecked by mc's plot armor or unnatural growth)

Idt either resolving the problem fast or slow can be said to be the best in every situations. Each time it depends on the situation: level of threat, personality of characters,etc.
Looking for global optimum strategy isn't really relevant if we know the characters have restrictions and they would never have thought of or executed those strategy for any personal reason.

For example against the knight, mc's comportment clearly shows that he isn't someone really that concerned with having the best solution. If he didnt troll during the whole thing, he would most likely have looked more respectable.
Having fun, staying true to himself, maybe the thrill of doing "hero saves the day" kinda things are all good enougth reasons for me.