Let me throw some things out there that I know you know... but maybe you haven't thought of owning a Stallion with these thoughts in mind.

In the wild the Stallion is the leader, the fighter and the lover. His goal is to maintain and increase the numbers in his harem through breeding and fighting to steal mares from other herds. He will not tolerate other stallions breeding his mares or challenging his position. In this stance he is much like an African Lion! Mares that are unruly get put in their place quickly. In "our world" geldings may be tolerated, but they may also be perceived as competition.

Now step into the picture and see the problem. You are telling him that YOU are the leader. YOU tell him when to breed. YOU decide he must not fight - ever. See the conflicts? With Stallions we are constantly asking them to behave outside of normal horse behavior. For some animals/breeds, this is less of a problem than others. As an example, Andalusian Stallions have long been bred to behave. In Spain, only the stallions (and occasional geldings) are ridden, mares (generally speaking) are not. Arabian Stallions, on the other hand, are a huge handful as a breed. And of course it then varies from animal to animal.

So maybe thinking about it this way will help you to see what everyone is talking about.