As an introduction to the art this is a very valuable tool.
Also, advancing technology should soon allow digital animators to do 3D compositions from film.
I've already seen CAD drawing programs that render flat 2D motion drawings into 3D animations.
Doing that with O-Sensei's old film footage should allow CGI programmers the ability to make a competent 3-D animation of what he is doing.
Being able to see O-Sensei's Aikido in 3-D form on a computer would be awesome.
I hope to see this done sometime in the next 20 years.