1. A martial art is intertwined with the culture it originated from. You can not separate the two, even if it's only restricting yourself to using English terminology, without losing part of it. It's not just about the techniques.
I'll agree with that. Embracing the culture is a significant part of truely understanding a martial art and the history or lineage behind it.
2. A martial artist should not go against the wishes of his seniors and instructors. Like it or not, resepect is a big part of the arts that are handed down to us; being disrespectful, such as pursuing training methods you have been told not to do, is a very big no-no.
I'll agree that respect is needed and earned in the student - teacher relationship but at some point the student needs to step forth on his own. If it is appropriate for a student to flounder and learn a new technique by experimentation, why would it be different for fledgling teachers? I think its an easy case to make that being a good teacher is more difficult than being an apt pupil.
Perhaps looking at revising the methods in which people are taught martial arts should be viewed more as one of those things that let new teachers become experienced teachers. Ultimately, their students will correct the teacher if the method is unacceptable. We do not live a world where trainers and options are few and a bad choice could lead to death on the battlefield.
I actually agree in part with your counterarguments but I would like to suggest that neither argument prevents a change in teaching style. You can respect the spirit, tradition and honor your teacher while still placing your mark on your students in your methods. You can still cherish and celebrate the culture that is a part of your art and it will not have to impact on your training method.
You must learn the basics and the concepts of that art before you can start to refine and improvise. Don's main point I take to be that traditional style MA's *are* valuable and do have much to pass on to future students. Yet the methods that are used to teach these arts that take on a traditional bend may not be suitable for the modern world. Is it better to let a traditional style art lose its students or make small changes to keep it accessible? Am I describing a slippery slope? Yes but things cannot stay static forever.
In my neighborhood we have Shinto temples that are falling into this exact scenario. They have not tried in any way in the past to increase their memberships. The generation that supported them is passing on and the children are not Shinto but instead are Christian or possibly Buddhist. So what is left for them? Simply wait until the last member dies so they can close the gates? Or maybe do what they are trying now, gathering up the several smaller shrines to try and consolodate membership. *Change* the way they think about how their organization has and will survive. Make a concerted effort to not recruit people just to give money but to continue spreading their philosophy and teachings. Aikido is not in this situation yet, but is it wise to wait until the day it is to start addressing problems?
If the whole real arguement is about sparring, what would you call practice throws? If the uke and nage agree to increase the speed and tempo at what point will it stop being "practice" and become sparring with someone taking the fall?