Megan at aenterspooking.blogspot.com did a great blog hop about equestrian opinions held for a long time that are just totally and completely wrong. Let me count the ways baby...
Then...The head set is all and the body will follow.
Now...The body is all and the head will be in the right place if the connection is human body to horse body.
Then...Use whatever bit/training aid to get the effect you desire.
Now...Use whatever bit/training aid to get the effect you desire but realize it is a band aid over training that is not correct and/or complete. Use these things temporarily, maybe for safety, but always be working to fix the holes in the horse's training, so they are not necessary.
Then...My trainer is good at some things, so that must mean he/she is right about every single thing.
Now...My trainer is good at some things but everyone has their weaknesses, so have an enquiring mind while respecting what they know and do well.
Then...Some riders are just talented and the rest of us will never catch up.
Now...Some riders are much more talented but with good biomechanics, good instruction, and an enquiring mind good things can really happen.
Then...Get the behavior or movement you need/want to get even if it is rough/nasty and smoothing it up will be no problem.
Now...Structure the work so every step builds to the next step and even first tries at new things will go pretty well because you have the prerequisites.
Then...Money=success(and horse happiness).
Now...Money smooths over a lot BUT you still see some very wealthy amateurs that still ride poorly on their fancy warmbloods, do well in competition, but seem kind of cranky and some "lower middle class" riders on their off breed dressage horses that ride very correctly, don't win everything, but seem really happy with their lot in life.
Then...If I ride at X level I will be a success and considered a good rider.
Now...If I am in harmony with my horse, he likes his job, and we have a great partnership it doesn't matter if we are not at the summit of the dressage mountain. Without harmony and partnership the summit means nothing.
Then...If you are a good enough rider and trainer you can work with just about any horse.
Now..If you are a good enough rider/trainer you CAN work with just about any horse but the question becomes do you want to? Is it worth the effort? Might your time be spent more wisely with a horse that wants to work with you and try?
I could go on pretty endlessly. What's on your wrong opinions list?