Faye synthetic musks are not the same nor do they function the same as a natural pheromone. Secondly in actual fact certain types are know to be hormone inhibitors in actual fact.
As always I try to keep an open mind so if you have knowledge of a study showing the effect of musks on the sexual arousal of colts then I would love to read it. At present I would argue that if this was the case then we wouldn't even be able to wash our clothes as most fabric detergents are also full of them so would cause the same reaction as your perfume. As I say a much more logical cause of a reaction to the perfume is the masking of the horses natural ability to pick up scents elsewhere such as an approaching predator. This is why wind makes horses spooky I believe. The constantly changing wind, masks the direction of scents and makes it more difficult to hear. Thereby making horses more twitchy. ( a bit like humans in the dark as we rely on sight so much)
As for a chimney we will have to agree to disagree. I see your point and your experiences. That's fine I just cannot agree with them. In Argentina they use a piece of wire over the nose as 'an anti-rearing bit'. Does that make it right?
Interestingly that's part of the problem with handling horses, we look to the solution and not the cause too often.
Traditional and NH handlers are looking at techniques or methods to treat a problem, without looking at the cause. It's amazing how so many of these horses are on sports yards isn't it?
If a horse is being aggressive (usually caused by a history of human intervention) then the first thing I do is give him space to attack. Yes attack. I am present and stand my ground but offer no pain or counterattack. That is incredibly powerful, because the horse has given his all, he has been able to express his power and emotions, and here is someone who has stood his ground but not tried to overpower him back. Usually they settle and follow within minutes. Problem resolved and the foundation is set for ever more in just those few minutes.