Bernie is an old, old friend of mine. I've known him since I moved to Seattle in 1981. Bernie was a student of Yoshioka Sensei in Hawaii originally. His shift to a different way of running his techniques didn't come about simply due to techniques that didn't work... if I remember what he told me there were techniques that worked too well i.e. the subject was injured because he had no ukemi training.
Bernie's technique was adjusted to increase the pain factor without increasing the impact on the subject. I had the fortune to take ukemi for him a few times at demos and I have to say, it was entirely unpleasant. He'd pinch, torque, and otherwise "persuade" you into compliance. You'd have to be on meth not to react to his various tricks.
Despite Bernie's change of name to Aikijutsu, I never found anything he did to be the least incompatible with what I had been taught by Saotome Sensei. It was just a very "applied" form of Aikido. I think that Bernie was largely reacting against what he saw as the move towards a less than martial Aikido, especially on the West Coast.
I think you can still get his videos here: Bernie Lau Videos
Interestingly, it was Robert Koga who first taught Aikido based defensive tactics to the LAPD back in the sixties. He founded the Koga Institute and continues to teach to this day I believe. He is by far the most influential of the Aikido teachers who have put their stuff out for the law enforcement and security community. The US Secret Service incorporated much of his material into their training with great success. I recently had a conversation with a retired agent in which he commented on the similarity between what I taught on my Defensive tactics video and what they had been taught. When he told me that they had done some training with Robert Koga, I said that explained it...
Website: Koga Institute
He has a very fine set of videos available for anyone interested in the practical application of technique.
The other Aikido teacher who had a fully developed defensive tactics system was David Dye. He appeared at the second Aiki Expo where he taught a class. He started as a Yoshinkan practitioner although he has now founded his own style. He was a Costa Mesa police officer for years. He also has a collection of videos, available from Budovideos.com, I believe, which outline his DT system. Once again, it's straight Aikido with a practical application bent.
Website: David Dye
The perpetual discussion of Aikido application in the so-called "real world" would tone down a bit if folks were familiar with the work these men have done. All their stuff has been done on the street with real bad guys. It's practically oriented but it is straight Aikido.