Actually his "function" is his strong connection to the aikikai/hombu. As shihan he is the link - or maybe one strong link beside others. And his loyalty to hombu/aikikai is kind of paradigmatic. And he is like a door opener for Europeans at hombu. Or at least used to be for a lot of teacher I know who got their letter of recommendation from him. And, kind of other way round, as far as I know he was the one who invited Endo seishiro for the first time in Europe?
This is part of the problem - as people like this pass away the links and the personal relationships with hombu are disappearing. Since the Aikikai model has always depended heavily on these relationships, this is a serious problem for them.
Now you have organizations run by people with no personal ties to hombu. What is their motivation to remain affiliated?