Well, When I first got her, she went into her first heat and was a raging lunatic, nickering and squirting at anything that moved, including people! So, I started her on it and had her on it for a few months, and I barely noticed her heats after that. Then, I ran out of it, so I thought 'ok, we'll see if its actually doing anything before I buy more'. She went into heat and was again a lunatic, nickering and squirting at everything, totally distracted. So, I started her on it again and she's back to herself. I have no doubt about whether it works, it drastically makes a difference. And I'm such a cheapskate, it has to work really well in order for me to spend money on it!
My pinto was like that when I first got her - and my vet who specializes in breeding/mares/stallions told me that its very common behavior in mares when moved to a new place with new horses.
The following year all the behavior had gone away on its own.
How you ride is how your horse acts =) My friend has a 30yr old Arabian Thoughobred cross. I can get on her and have a snaffle on her with loose rein and be able to fly her through some barrels, pull her down to a sedate walk around the field, take her out on the trails. Friend gets on her, has to have a really strong bit, curb chains and the whole **** ride the horses is flighty, tense, and on trails will spin around and try to head for home. Until we switch horses again lol, then she's good and my old boy, who never acts up anymore. Becomes a demon from hell like he used to in his young days =) Its because she herself is always tense, even if her reins are lose her hands are tight, back stiff, she just rides expecting trouble, therefor. She gets trouble from every horse she rides
I don't think that Tessa has a riding or handling problem with her mare - from the way she describes her its exactly the same as my pinto was - a total hussy when she's in season, flirting with other horses, squirting at anything that moves and likely getting herself kicked as they irritate the others with their unwanted advances!!