This is, I think, the overall issue. People know that Aikido is effective to help other arts, provide new movements, etc. and I have no way to prove it, but I also have no way to disprove it or reason to doubt it. The issue that I have is those who claim it is a self-defense system on it's own, since that's ignoring the whole 'effective to help other arts' aspect of it.This may be true, and if so, suggests the sales pitch is very misleading.