"You want [the horse] to relax in halt but as soon as you put your leg on, switch on and go forward. When he goes into trot, just give him one more touch with your leg to let him know you really want him to go forward. When you are going forward and coming back, ask yourself was it the reaction I wanted? If you are doing it halfways, then you are always compromising with him." ~ Nathalie zu Sayn-Wittgenstein
"So many riders think only about the physical aspects of training and I hear too many times from riders, ‘well my horse just needs to get stronger’. I ask myself constantly what about the mental part? My idea is that the physical part is 25 per cent and the mental part 75 per cent and I find myself asking each and every day, did my horse really understand what I was asking for?" ~ Steffen Peters
"When you do something too much, too long, it’s called drilling. That’s not a good word with horses. If it’s not perfect it's ok. We have tomorrow, we have next week. Don’t be excessive with the horse." - George Morris
A good contact with the horse's mouth usually only occurs if the rider also has good contact with their seat and legs. When a rider tries to keep rein contact with their legs completely off, the horse will usually resist or try to avoid the rider's hand.
"I really want to emphasize that a rider first rides a horse with the legs and seat; then come the rein aids, as a support to the seat and legs. These three things together subsequently determine the quality contact that leads to the complete harmony and understanding between the horse and rider." ~ Johann Hinnemann
Slipping the reins in the final strides in front of a drop into water must be done gradually and inconspicuously. Too much or doing it at the last second, and you will effect the horse's balance.
When working with a horse that does not have a great natural lengthening, make sure that you don't ask for too much too soon. Compare this to a singer who is training their vocal cords… They gradually expand their vocal range until they hit their limit. This helps to prevent them from overextending themselves, and builds up confidence in their abilities.
If you ask for too much angle in any lateral movement (more than your horse can handle at that moment,) you risk impeding the balance and fluidity of the movement, which should be one of your top priorities.
"Lesson quote of the day (in reference to her horse being crooked) - He feels like two men in a horse suit who aren't speaking to each other! (identity of student being protected :)" ~ Carrie Wehle
"Many riders in the name of impulsion, put too much tension in their horses. Others in the name of lightness, have their horse 'abandoned' (without a sufficient connection). The truth of equitation is in between those two extremes." ~ Nuno Oliveira
When trying to improve the activity and engagement of your horse's hind legs in downward transitions, think of a trot in place and dancing your way to the walk or halt.
"One of the goals of dressage is to recreate the natural beauty of the horse’s gaits under the rider, so that the horse moves as beautifully under the weight of the rider as he does at liberty. In order to achieve this, the swinging of the horse’s back has to pass through the seat of the rider undiminished. The back has to be able to rise and fall with the same ease, regardless of the rider’s presence. If the rider merely sits passively, his weight alone can sometimes be enough to diminish the freedom of movement of the horse’s back. In these moments, the rider has to enhance the upswing of the horse’s back with an active contraction of his abdominal muscles, which helps the rider’s pelvis to swing more forward-upward, without tilting forward, however." ~ Thomas Ritter
"The half halt is essential to change the horse’s balance because it creates engagement. Engagement has two parts. First, the horse carries more weight behind by shifting back onto the hind end. Then, because he activates his core muscles, he is able to lift the forehand." ~ Kathy Connelly
"You’re not going to get a quicker reaction by digging in your spur. If you’re standing on one foot and someone comes behind you and scares you, you’re not going to put your foot higher in the air. You’re going to put it on the ground." ~ Robert Dover
Many horses need to be in true self carriage to regularly jump cleanly in the show jumping phase. Meaning that you have to be able to soften the reins in front of each jump without the horse changing their canter.
"The engine has got to be revving, and then you put your pedal to the floor and it will go. Sometimes you have to get the engine screaming." ~ Chris Bartle
The horse shows improved self carriage and more expression and cadence in his gaits, not as a result of the rider doing more, but by the horse doing more and the rider less and less.
In no way does holding a horses neck in a position build up correct muscle. The topline muscles that you are looking for are only developed by the horse using his whole body correctly. Which will not be achieved by using the reins, or a gadget like draw reins, to hold the horse's head down.
Don't confuse being left behind over a jump with a defensive seat on cross country. They are very different. The rider who is in a defensive position on cross country is a nickel behind the motion, while still not interfering with the horse in any way. The rider who is left behind is catching the horse in the mouth and slamming their backs on landing, both the ultimate punishment for the horse jumping the fence. If you are getting left behind often, it may be time to move down a level and work on your basics.