My point is that translated original documents, interviews with direct students, and a smattering of footage and photographs are completely insufficient to know what it was that Ueshiba was doing.
It you therefore go to internal Chinese martial arts to develop material that looks like it might be similar to what is suggested by these translations, films, and photos, it is a misrepresentation to say you are teaching "Ueshiba's aiki."
Ok I think I understand your argument.
I think what others might counter with is if Ueshiba's aiki, is substantially different from Sagawa's Aiki given a common root source,? Likewise, how much overlap there may be between something like what CXW or Sam Chin or others are doing? I think it would be fair to say that there are different flavours/interpretations of the skills IS folks are trying to build and presumably, one could develop aiki but it may be flavored differently than that of Ueshibia do to different life experiences, training paradigms etc. I think Mike Sigman was trying to cover this concept in his baseline skills thread years back saying there are some commonalities between different IS approaches, even if the eventual skills may have different levels or results.
This however seems to be a different argument, than the one the IS proponents are presenting. In using the phrase Ueshiba's Aiki, they are referring to Aiki in the internal martial arts context, and that Ueshiba was utilizing Internal training principles and methods. I don't think they are claiming that there is only one aiki, or they are doing the exact same flavor as Ueshiba, rather aiki as expressed as martial arts principle, in which case one could look to translations, films and photos for evidence.