Peter A Goldsbury
I think this is a complex question and there are no ready answers. In the column I have tried to present the evidence that Morihei Ueshiba considered Iwama to be a special place, where he consorted with his tutelary deities. In my opinion, he regarded his own training with weapons: sho-chiku-bai no ken, to be an essential part of this association--at least at this time. Notice that I have not said "taught". Rather, he appears to have trained with Saito Shihan as his partner.
Apart from the Kumano Juku, of Mr Hikitsuchi, Iwama seems to be the only dojo where was such an intense focus on weapons, especially sword--at least for a decade or so, until he started to visit other places, and until weapons came to have lessening importance later in his life. There is also the undoubted fact that he had in effect given over the Tokyo Dojo to Kisshomaru and did not interfere with the running of the dojo. Of course, he would teach there, and taught there increasingly often, but the Tokyo Dojo was not a laboratory/shrine for him.
It is true, however, that nearly all his senior students did train with weapons--and developed their own systems. Saito Sensei was preeminent, but not the only one to do so.
I have not really answered your question, but I do not think that Ueshiba's occasional anger at bad practice amounts to a total ban on teaching weapons outside Iwama. I think you would need to search out the interviews with the senior students like Tamura and Tada Shihans.
I have written about this else where but it is relevant to the discussion here... In the post war period you see a divergence between the training offered to the general student body and the training offered the students considered as the uchi deshi at the Hombu Dojo (the fact that these people might not have been the same kind of "uchi deshi" as the prewar deshi is another discussion that's been made at length).
My exposure to post war uchi deshi comes via my exposure to three of the students from that time, namely, my own teacher, Saotome Sensei, my Assistant Chief Instructor's (Kevin Lam) teacher, Imaizumi Sensei, and Chiba Sensei.
Both Kevin Lam and I were both told that there were sword classes of an optional nature that were made available to interested uchi deshi at the Hombu Dojo. Clearly, teachers like Yamada Sensei, although of the same generation, chose to not attend as there is no evidence of this in their teaching.
Both Kevin and I asked who taught these classes and were immediately rewarded with responses that strongly resembled the testimony at the Watergate hearings. In other words, no answer was given, memories were suddenly cloudy (this from people who normally remembered everything about their training in those years with great clarity).
The fact remains that both Saotome Sensei have a bunch of sword material which clearly came from Kashima, Yagyu and Itto Ryu sources. Saotome Sensei's, as is his wont, has been highly personalized. His forms are his own but the elements came from somewhere and are very different from Saito Sensei's work at Iwama. However, Imaizumi Sensei's students actually have notebooks with forms that are straight out of Itto Ryu and Imaizumi Sensei never studied Itto Ryu formally.
Chiba Sensei also has quite a lot of sword work that does not resemble to any large degree what was taught at Iwama, although he also has some that does seem to derive from that work. I was never able to ask him about where he learned his sword. I am not directly familiar with Kanai sensei's sword work but he had the reputation of being an excellent swordsman and he was of that same generation as well.
Anyway, it is my own guess that O-Sensei, and perhaps also his son, Kisshomaru, arranged for instructors to come in and do classes for some of the deshi. That is the only way I can account for material in their sword work that clearly derived from various koryu, even ryu that no one seems to think O-Sensei had studied... It isn't even a matter of individuals sneaking off to study sword elsewhere, as did happen as I understand it, because there are tremendous similarities between what the deshi at this time put into their sword work (the ones who did much sword anyway).
I think it is very much a mistake to think that O-Sensei discouraged weapons training outside of Iwama. The evidence would run counter to that. Although all of the uchi deshi from Hombu had the chance to train at Iwama regularly when they attended O-Sensei during his stays there, at least the teachers I mentioned have a large body of material which did not come from that training.
Given O-Sensei's unstructured style of teaching, there is no way that this material was simply acquired in the instructor classes offered by the Founder. So I am left with the fact that this material exists, no one will say exactly where it came from, it must have been sanctioned by the Founder or at the very least, his son, and that this training was not offered to everyone training at the Hombu Dojo because only a very small number of folks seems to have done it.
So, whereas weapons training became downgraded and even removed from Hombu's general instructional offering over time, it is clear to me that weapons training was considered important for the developing professional instructors when O-Sensei was still alive. Those teachers from that period who journeyed overseas maintained that emphasis with their students. Each of the teachers I mentioned has produced students who are quite capable, at least by Aikido standards, in their weapons work.
In the face of all of this, I cannot see how one could maintain that weapons training was discouraged outside of Hombu or that the Founder did not want people doing weapons training.