Originally Posted by Horsesdontlie
From what I've heard the reason why Impressive was so 'good' as a halter horse was because the constant muscle spasms help develop muscle, and a lot of it. It helps make for beefy horses, kind of like hereditary steroids with lots of nasty side affects.
Why need a halter horse that is so beefy like that in the first place? I don't know. At the cost of the extreme suffering of tons of horses, just to force them to bulk up. =\
This is exactly why they breed for N/H horses. The N/N Impressive horses don't have the genetic "advantage" (using that term with full sarcasm and disdain dripping) that the N/H and H/H horses do - the muscles are very defined and often big - gives them a boost in preparing for classes where muscles are everything. H/H horses don't live long, so they hope for N/H horses.
I myself had a N/H gelding - years ago and didn't know when I got him. He was actually pleasure bred, except for one Impressive grand-dam. They pass it down 50/50 though, so even though his name was Zippos To Ride, and went to Zippo Pine Bar four times, he ended up with it. Moved like a pleasure horse, looked like a Zippo, but had very defined muscles. Sold him with full disclosure after learning of the risks - he had won me enough that a trainer took a chance with him. Seemed like a time bomb waiting to go off... and I sold him for THOUSANDS less than I could have had he not had it. Everyone was very, very interested until they learned his HYPP status.