hmm... very thought provoking. Just finished the book and tried to understand where I stand since I'm all pro Klaus Hempfling but agree with everything she says as well and their ideas aren't on the same page on first glance.
After some probing into my own wreck of a brain I finally found the difference. Basically the difference is only in the use of dominance. Imke deals with all horses as fully mature creatures, letting the horse's natural respect for the weaker link to keep her safe. i.e. a horses will always run at the speed of the slowest in the herd and will contain their streght when playing with weaker horses. Add to that her calm, wise leader posture and you've got a safe productive relationship.
Klaus however, deals with all horses as not fully mature creatures and acts with the sort of dominance a parent would use. He calls is lead stallion dominance but a lead stallion would very likely be much more agressive. Like a decent parent, Klaus shows dominance on the same grade as friendship, leadership and unconditioned support. He feels like home to a horse and that's how we feel about considerate parents. With time, friendship and leadership outgrow dominance as the horse matures and no longer feels the need to prove himself to you all the time.
Personally, I find Klaus approach safer. Mares tend to mentally mature quite fast and it's very easy for me to put them at the same level as myself and disregard dominant issues completely. We understand each other, we respect each other and all goes smooth if those 2 pillars are well maintained. As for stallions, after their teens I find it possible to almost reach this level, but never quite so, and with younger stallions that's a big NONO. It's not by chance that in the wild they don't get their own herd before that age! sure they are phisically mature by the age of 6-7, but they still act like spoilt brats! What lady would wanna put up with that? So, same way my parents did with me, dominance it is untill I was wise and mature enough for them to trust our relationship to respect and friendship alone.
anyway, that's my point of view... might just be my personality clouding my judgement, who knows? I do tend to take care of everybody as they where my children, be it my parents, cousins, siblings, friends, pets, whatever, It's just how I've always been. Schoolmates used to call me the guard dog (cos i'm so protective). Horses seem to like that! though I still find it extremely stupid of them to hide behind puny me, but oh well, if that makes them feel safe, all the less trouble for us...

Oh, another note on this book. Although the horses in the book aren't the best examples to show her knolage (phisical atributes only allow so much), she does have a big advantage to Klaus because she opted to study the great classical masters instead of simply disregarding them. This leads to a good few insights on teaching a horse to better balance and collect himself. I would simply adore to see how a well built Lusitano stallion would come out from her work. Should be quite a sight. Yet I still wonder how much sparkle she could incite in a stallion when she insists on bluntly showing her weakness to the horse. I never saw a stallion show off to an obviously weaker creature, only to those who are at the same level or slightly higher. Too Hight and they will shut down...