I know many of the reality based self defence folk have a dismissive attitude for Aikido because it lacks realistic attacks. The attacks in Aikido represent lines of force but there is truth to the fact they don’t look much like real assaults; however, there is a lot to be learned from Aikido.
And on that I recommend: “Aikido and the Dynamic Sphere: An illustrated Introduction” BY A. Westbrook and O. Ratti (Illustrations by O. Ratti)
There are other good Aikido books but I think this one goes into the principles better than most. Most give a history of the founder and Aikido then go into techniques. This book does have at the beginning the philosophy, ranking etc. but they don’t spend a lot of time on it.
As for the usefulness of it I recall having a VHS tape series (yes, I am old) by a police officer showing how he used Aikido in his law enforcement practice. Like all martial arts they were devised for self defence and can be used for that when applied properly.
But the truth is I don’t care if Aikido can be used for self defence (it can) because many of the principles they use can be applied regardless of your style or system.
I wrote and entire book called “Now You See It, Now You Don’t” on using empty space for self defence and I see Aikido as one of the two styles I believe make the best use of empty space (BJJ is the other.) I love watching good Aikido for the beauty and utility of their use of empty space.
I do have to say that there will always be a section on Ki (chi or qi) in a book on Aikido and that too throws off many but if you think of their description of Ki not of some energy force but as a way to visualize the use of your intent or the intent of the Aggressor then you can find a practical use.
Once their principles are covered as always, they will head into techniques and for me the actual technique is immaterial to their movement and use of empty space. That is where the true value lies and how you can take those principles or the under lying engine and use them in your own way. This is the great value I see in Aikido and why I think it is a value in looking at this practice. Much can be learned.
A final word or two. I know in Aikido there is often a wrist grab and people criticize them for this as well saying they are uncommon and they would just let go. I can’t say they are common but then I know in grappling you work of wrist control…. As for letting go – no you won’t and historically for Aikido you sure would not. Why won’t you let go? Why did you grab them? You grabbed them to hang on and if you are really trying to hang on to control them then the move is over before you think of letting go. I’ve done this to people telling them to not let go don’t go hang on tight then…. It is over. The other thing to remember (this comes from Rick Bottomley) is that Aikido comes from Jujitsu which was a battlefield system so when they grabbed a person’s wrist to control them it was because they had lost their weapon and were grabbing the arm holding a sword or knife. Now if you have grabbed a arm holding a knife how quickly will you be letting go?
Once again don’t worry about the type of attack or the specific response to the attack, look for the underlying movements and principles and use of empty space and I believe you will find this something you can learn good things from.