Some of the best mannered stallions I have ever dealt with have been pasture bred ones. I tend to believe this form of breeding can help a stallion understand he doesn't just get to jump on other horses (mares will only generally allow a cover when they are ready... Not on his whim)... But that doesn't mean pasture bred stallions are the only ones who are capable of being well mannered.
Remember that most stallions have a low BS threshold... So don't nag nag nag at him, he could take that as aggression on your part and meet it with equal mentality. Always insist that he be well mannered (pay attention to him, and correct the little things SOFTLY, rather than wait for him to be truly naughty and have to "punish" him) I usually find soft is the key to having a soft horse, regardless of sex.
Stallions can be easily distracted, so keep him thinking about you and what you are asking next... Don't get into a lull and start daydreaming then be suprised if he chooses to tune you out in a critical moment, he needs to be able to see you and trust you as his leader - otherwise he won't respect you as his leader when a situation arises that triggers his testosterone induced instincts... Do it by being quiet, firm and keeping things new and interesting for him.