You are forgetting the fact you lose less CS per man when you have less men. If you have 10 men, you maintain over 90% of your CS. At 50, you are down to 50%. At 100, you are down to 40% due to diminishing return. That is why it is wise to have multiple small militia units than 1 large one most of the time.
Having 38 nobles leading 30 men each is much better than 11 people leading 100 men each.
Maybe during the initial battle. After that first battle, those 38 nobles will be down to 10 healthy troops each, while most of the other 11 nobles will still have 50+ troops because they retreated early. As casualties go up, the small unit's CS will quickly go down to 0, while the larger unit's CS will not decrease that much, because fewer troops means less diminishing return. After a few more battles, the 11 nobles might be down to 30 troops each, but the 38 nobles will have almost no troops left. Guess which side will end up retreating? Guess which side will end up with more nobles wounded or captured?
Smaller units win battles. Larger units win wars.
