It seems that the root of our disagreement is not so much different ideas about aikido as different understandings of what it means to cause pain, because I agree with most of this.
Actually, our approach to Aiki is probably different as well. What we do is rather unlike anything I've seen in Japan or the U.S. This is one reason I don't call what we do "Aikido," but rather Aikibudo. This is reflected by my teacher as well.
Not only should technique not hurt, ideally, uke shouldn't be able to feel what is happening at all.