First off, to understand this post it would probably be helpful to read horsemom's post from Of horses and boys... and everytihng in between.
Personally, I agree with everything she's said, but I've found that when a rider has contact (Note: contact does not mean pressure; the rider should be able to give both reins and have the horse maintain the same position. Otherwise they don't have contact and but are simply holding. Contact is simply referring to not having loops in your reins) and asks a horse to bend, the horse will (at least many of the horses that I've ridden... not all, but many) bend and end up in frame. There are two key points to this:
1) The bend I'm referring to does not mean that the horse can turn their head and neck to the inside, or to whichever direction you're asking them to bend, though that is a part of it. Instead, bend is referring to suppleness through the jaw, poll, neck, and body, and allowing the rider to direct/manipulate this into straightness. After all, bend really isn't about bending, so much as staying straight.
2)This 'frame' (at least in a young/green horse) will (and should not) be poll high. A young horse will not naturally come with the muscle to carry that. As time goes on and the horse learns to carry him/herself, the neck should naturally come up as the horse begins to transfer weight from their forehand onto their haunches, thus beginning collection.
I personally don't believe that you can say something is right or wrong based on where the highest point in the horses neck is. I may very well be wrong, and if someone would like to educate me on the physiology behind this, I'd really appreciate it. (Personally, I'd like to learn more about it from a structural musculoskeletal perspective. What allows a horse to engage their haunches and lift their back? When a horse is engaged, (sans rider) where is their natural headset? How loose is the horse's neck during this time?) However, I've found that many people seem to focus largely on the high point in the neck (yes, other things do come with this , but I'm saying overall, not specifically... if that makes any sense) and forget about the rest of it. They're just as focused on the 'look' as the rest of the world, their reasoning behind it is just a bit different.