One of the many ways that good Dressage will improve your jumping is increased straightness. Only when they are truly loading both hind legs equally will your horse have the chance to jump in his best form.
Moving the bit around in the horse's mouth to keep him from bracing against it is preventing the symptom without addressing the underlying cause. With that approach you will never solve your connection issue.
"If a horse takes responsibility for the fence too early, ask him to be patient and wait on the approach. On a 5 stride distance ask for a quiet easy 6 strides." ~ Eric Smiley
"Contact doesn't only refer to the hands, reins, and bit, but to the whole rider. A rider must give the horse contact through his entire seat. This means that his legs must lay gently against the horse's body, his seat must be balanced and supple, and his arms and hands must follow the horse's movement quietly and evenly. This create a smooth cycle of movement as the horse takes the rider with him. Only this then creates contact." ~ Klaus Balkenhol
Riding the half pass can help to develop the brilliance of the extended trot, by increasing hip and stifle flexibility, and freeing up the horse's shoulders.
"If you take a young horse and go on training in the way of - shortening the neck, never giving him the chance to develop step by step, if you make him short, and to come up in front, you end up with a real problem. If you look at a horse that has been ridden like this for ten years, you will end up with a back that is very hollow." ~ Gerd Heuschmann
"I discovered that the horse is life itself, a metaphor; but also an example of life's mystery and unpredictability, of life's generosity and beauty, a worthy object if repeated and ever changing contemplation." ~ Jane Smiley
You should know where your horse is going to land from a jump before he takes off. How? The type of canter in the final strides of the approach will dictate the shape of your horse's jumping effort, and the trajectory of his jump.
You can't assume that a horse with a low head and neck is heavy on the forehand, any more than you can assume that a horse with a high head carriage is truly collected. You have to look at the whole picture.
You need a short bouncy energetic canter in water. Not just to the jump in, but to any jump out or otherwise related to the water. Getting long and flat in the canter stride can be especially disastrous at a water jump.
"The horse must perform from joy, not subservience. Praising a horse frequently with voice, a gentle pat, or relaxing the reins is very important to keep the horse interested and willing." ~ Klaus Balkenhol
Think of that girth tight against your horse's side… after a while he tunes that out and barely notices it. The same will happen with your legs if they are always tightly clamped on his sides.
"There is no miracle. There is no magic wand. It is just education, trying to be as clear to the horses as you can. When I give an aid, is the horse going to understand?" ~ Emile Faurie
"Trust and respect are two-way streets. We want the horse to accept us as leaders of the herd, to guide them safely and to provide protection and comfort. In return, they will give us their respect, and willing submission to our ideas about what to do next, and when and where. But this respect can only be based on well deserved trust." ~ Walter Zettl
"Create a work station on your yard, where everything to do with work happens – for example, tacking up and washing off – and keep his stable for relaxation only. Then your horse knows he can totally relax when he's in his stable and won't be expected to work." ~ Carl Hester
"A major consideration concerning the horse’s posture in all lateral movements is the bend in the rib cage behind the withers. For achieving this bend is the foundation for the suppleness of the entire horse. One will never achieve this bend if one rides the lateral movements on four tracks too early, or if one tries to force these movements with crude aids, and if one forgets to reposition one’s legs in the transitions from one lateral movement to another." ~ Borries von Oeynhausen
When your horse gets too low with his head, it is NOT an effective correction to attempt to lift his head with your hands. Even if that does succeed in raising your horse's head, it creates a hollow back. Only lowering the quarters raises the front end correctly.
With horses that like tocurl their neck and become over bent, the rider needs to be careful not to get their reins too short. This will cause the horse to stay too short in the neck. Think of having longer arms that are always reaching towards the horse’s mouth.
"With the bend on the circles and in movements like the travers, it is important to use as little inside rein as possible. If you need the inside rein, there is something wrong with the earlier work." ~ Christoph Hess
The more you can find a deep, plugged in seat in the down phase of the rising trot, the more you can sort of "suck" the horse’s back up into your seat in the rising phase.
"It is wonderful to use the ‘forward and down’ stretching exercise as part of the daily work. We also must keep in mind a suitable balance between work and rest periods during any ride, and we need to schedule adequate days off work and days spent hacking outdoors. Physically tired or mentally soured horses don't learn much, other than ways of evading work." ~ Erik Herbermann
"I teach riders to adjust their reins within three strides on level ground (after a drop fence), and I want them seated between elements of a combination. This will give the rider more stability plus a wider and more sophisticated range of aids." ~ Jimmy Wofford
From Facebook fan Dana Ferguson ~ "Moving through the levels is really dependent on the bar that you raise for straightness. The more cognizant and careful you are to maintain it, the more the horse can work in true collection."
Be careful to not miss any possible opportunity to shorten your reins when your horse changes his balance in the direction of increased collection. If you do miss it, and are riding with a length of rein that was more appropriate to the longer, lower frame that you had previously... you risk losing the amount of increased collection that you had just attained.
Part of being a good cross country rider is having the ability to ride forward at the fences even when your horse is strong. Riding backwards at cross country complexes can cause all sorts of problems.
If you are using a stronger bit correctly you will be riding off of feather light aids. And that can be way kinder than ripping their face off with a snaffle bit.
"You are going to meet a fence one of three ways - short, right or long. Therefore you want to meet it on a stride that the horse can work from - a bouncy energetic canter - then he can add if he needs to and pat the ground, or say thanks for getting me here right." ~ Jimmy Wofford
"What is Feel? Feel is the invisible quality in every good rider who is communicating with her horse in harmony. She can perceive where the horse is during every step because he accepts the rider’s seat, leg and rein aids through the connection. The rider can then communicate with the horse in a stable, sensitive and relaxed manner." ~ Sarah Geikie
"Riders who lean back are driving the horse down in front. If they sit too strong, behind the vertical, then they are pushing the horse down, through and into the hand." ~ Carl Hester
"At its finest, horse and rider are joined not by tack, but by trust. Each is totally reliant upon the other. Each is the selfless guardian of the other’s very well being." ~ Michael Plumb
"First, [the rider] has to be ambitious. Mentally, he has to be well balanced and consistent. He has to be tougher on himself than on the horse. If he gets after the horse too much, he will not get far. One must really be able to push oneself harder than one ever pushes a horse. Then, success will follow…" ~ Ernst Hoyos
Everyone knows that we need our horses to be relaxed to perform well. But that starts with our own relaxation! A rider must be relaxed to give clear and precise aids to their horse, and to set the tone for the horse to be able to relax.
When you realize that you are meeting a jump on a half stride, it can be challenging to keep a calm, clear head! Give yourself something constructive to think about, by telling yourself to just stay still and keep riding your horse's hind legs all the way till the takeoff.
Dressage is natural for horses, but that does not mean it is always easy for them. Since we cannot explain to them why we are asking them to do things that require increased effort, and go against their natural instincts to do things in the easiest way possible - we must handle any inevitable resistances that might show up with patience in a quietly persistent manner.