Join Date: Feb 2012
Location: Alberta, Canada
I think its like people, as you get older you form more opinions, and are less likely to just take any advice thrown at you. A two year old typically is insecure in the herd, still learning how to use their bodies and how they fit in socially, so they are more likely to not challenge the rules. An older horse, especially a dominant older horse, knows where they stand in the herd, how big they are, and how to use themselves to their best advantage.
If you are starting horses the right way, earning their trust and respect, age doesn't really matter, other than having a physically mature horse you can just put to work, instead of a baby. Also once you've made a point with an older horse, its done. Young horses(like young people) naturally challenge the 'herd' as they are growing up and learning. By starting an older horse you avoid having to deal with the 'teenage' years under saddle.