Great stuff. Here's another must-have link on BJ. A pretty big series of photos taken with a high-speed camera. Some photos are taken with an exposure time of 1/100,000 sec. By Egerton of MIT at AG Spalding & Bros. in 1939
If you want to know more I can set you up with the son of the Director of Golf Research at the time. He has all the background. Among other things he has diagrams for clubhead speed and acceleration during the entire swing. Quite a feat even by today's standards.
http://www.clubmaker-online.com/bj01.html
Or go straight to the driver impact photo:
http://www.clubmaker-online.com/bj010r.html
Or a series of pictures showing a Dot 100 compression balata covered would ball from contact with the face until it leaves the face 4/10,000 of a second later
http://www.clubmaker-online.com/bj016a.html