Hi all. I do use the Parelli methods as well as clicker training and some John Lyons as well. I have also had a lot of hunter/jumper training in my background, as well as some dressage. I am an eclectic sort.
I do think there is a lot of wisdom in some of their stuff. The best thing, THE BEST, is that it gives you a ton of ideas of ways to play with your horse on the ground and not just riding. The Liberty and Horse Behavior course in a box is really good. Having spent my whole life studying horses, there were some subtleties that Linda points out that really made me think about things a bit differently. She has become a magnificent student of horse body language. This is valuable information no matter what training method you use.
I definitely use clicker training, piggybacked onto whatever method I am using. I also use the clicker training ideas of breaking things down into very small steps and training one criteria at a time.
I guess I am still thinking and experimenting with a range of training ideas. My biggest issue with clicker training is that it is supposed to be a training tool and the click is supposed to be faded out over time as a behavior is learned, but that is not how I see most clicker trainers use it. That is not to say that a horse loses a chance to earn treats, it should just get them for "new" learning and behaviors, instead of those it already knows. I am seeing some new work coming from this area that shows horses being rewarded for doing a new behavior by giving them a cue to do a behavior that already has a strong reinforcement history that is then rewarded. I like this idea a lot and need to think about how that could be expanded. I am also working on some ideas of alternate reinforcements with a different sort of marker signal (Peggy, if you read this, do you use anything like this? It would still work as a terminal bridge, but instead of a food reward would be petting, etc..definitely used on already learned behavior.).
If you are going to the World Show, you have been invited to the Parelli Celebration there. It would be very well worth it to attend if you can. The cost to other people is, I think, $99 for the show. I do think there is a lot to be learned. Just put the info in your toolbox, and don't throw the rest away if it is working for you.
More than anything, I love the way they bring the horses up into collection gradually, and they do have a very good way to teach this to people in a way that seems non-threatening. Going from Freestyle to Finesse with a soft touch, a soft feel, all very good stuff. I am working on this, overlaid with the clicker work, in teaching my riding horse. I am also studying the work of Karen Rohlf, who stems nicely off of the Parelli program. I think the Parelli program has made HUGE progress in the past few years since they started learning more with the help of dressage master, Walter Zettl. There is plenty to be learned in the program for people who are drivers, if you care to take the time to adapt it. It is there, if you look for it.