If you have good aiki as uke, it doesn't matter whether your arm is bent or locked out. Joint locks stop working with good aiki. Aiki as in the body skill. Course, if tori/nage has better aiki ...
heh, I was at Aikido tonight discussing this clip. [Not that Im that fluid in Hungarian, more like babbling with pantomime]
Anyway I brought up the point I made above, which I thought was valid - till our 1st kyu came over smiling, grabbed my wrist and put me on the ground. lol!
Yeah, that was after I had successfully demonstrated my point - or so I thought. So at the end of the day, arm straight or bent, you can nail the person... I just hadnt been shown how to do so up until now with the arm straight... emphasis has always been on the arm being bent, or I suppose going into another move as mentioned in a previous post.
... much to learn still.
[and happy thanksgiving...]
As for Aiki - I have tried something like the unbendable arm with Gokkyo [i.e., when your on the ground and Tori goes to pin your arm/wrist up by your head.] When I had my arm relaxed, yet extending it, my arm could not be bent. I did this with a couple of people and it was fun to see the results as it worked with higher lvl kyu as well. [something I tried on my own, they werent even expecting it, that is what was so cool about it.