Aikido being purely internal?
No martial art is all internal. Physical movements require some adaptation of external skills, but how they are done and how the energy used is applied is the "internal" part. There is a difference between being "fit" and being "external". "Getting in shape" is necessary for any physical activity (except keyboard mastery) so having a fit body gives you a "good vessel" to work with.
This would mean physical strength. I dont doubt his skill ability from what I have learned but he would still have had physical conditioning.
Where in the internal arts is there anything that teaches you not to be fit and strong? Do you use that as your technique... no... but there's nothing wrong with having strength, you only have to "unlearn" how to use it to use your internal strength.
I constantly tell people to "relax harder" when they're trying to muscle techniques... but I've never told one of them that they shouldn't lift weights, run, or do anything that's physical training. The better shape you're in, the better your chi flow is, and for the most part, your general health. The days I'm not in the dojo, I'm in the gym using the machines.... I just need to relax harder...
What man is a man that does not make the world a better place?... from "Kingdom of Heaven"