It's time to clear up some misconceptions. There are plenty of people out there who consider aikido as a "fighting" martial art. I am not among them.
Before every aikidoka in Asia calls me out, let me be very clear what I mean. I find it very sad that so many people come to aikido with false expectations about what they will and will not learn, and that is what I want to address. First and foremost, for the record, loud and clear, I want to say that I firmly believe aikido training is very important for anyone, martial artist or not. What we learn in aikido is of great benefit to achieve our potential as martial artists and as human beings. However, I do not classify it as a fighting art per se.
Even something like kamae, has no real practical application in a fight. Fights are dynamic movement. There is no time to seek and hold a full kamae shape. However, kamae practice - especially moving from shizentai (natural standing) into kamae is important to develop the habit of keeping the arms in the right shape and connection to our body no matter where/how we move. This is essential in aikido, because if the kamae hand is not strong, we cannot connect and control.
I can read your mind. You are thinking "If it is not a fighting art, why study it?"
My response is simple. Aikido is designed to teach you very practical combat concepts.
In aikido, these are not the techniques themselves. It is really about the concepts the techniques demonstrate that make them useful training tools. And those concepts are VITAL in becoming a good fighter. Technique is the least important part.
Any martial artist with practial experience can see that the attacks used in aikido are simplified and exaggerated. NOBODY really punches like that. It is not very often someone in a fight will bother to grab your wrist, grab both wrists from behind, etc. It is very rare that any of us will have to fight from a seated or kneeling posture. It is very unlikely to consider any of us being attacked with a sword. Again I would say that if we only look at the combat practicality of each specific aikido technique, we will find ourselves disappointed, since aikido as it is commonly taught, is not a combat style. This is done purposefully. If it was not that way, we would only study the techniques (a la Krav Maga) and miss the chance to deeply understand the important concepts and principles that make ANY technique work. We would be distracted. Caught up in the minutea and missing the big picture. The big picture is what we must learn to see.
So...what are these important principles of which I speak? Let's take a look:
1) Body posture/weight shift/balance control
Almost all the techniques are designed to help us learn how to move forward confidently with balance and control, and to shift our weight from one foot to the other using the knees and hips. Great examples of this are tai no henko, hiriki no yosei, shumatsu dosa, ukemi, kamae.
For aikido to work as a fighting concept, we need to be connected to uke. In every technique, we are exploring how to stay connected to uke while we both move. We want to be glued together until the technique ends, so that uke can be controlled and put where we want them to be. When the connection is lost, we learn how to reconnect so control can be maintained.
Based on the connection, we learn how to control uke's body (torso and head) by connecting to their wrist. Too often, aikidoka think only about the wrist and forget that the whole point is to control uke's body so that it can be moved off balance. Ikkajo, Nikkajo, Sankajo, Yonkajo all control uke's torso using different contact points and principles.
Many of the techniques have a leading element. This is not the same as pulling. When we lead, we actually have to match the speed of uke's attack. Practicing this is how we learn our timing. Having done so, we direct uke to a position where their balance can be taken.
5) Taking Balance
Every technique has as a principal feature the taking of uke's balance. Without doing so, uke cannot be thrown. It is important to look for the balance points and use our techniques to put uke into unbalance, from which they can be controlled.
6) The Line of Power
Posture is what gives us power. When we bend forward or lean sideways, or allow our structure to be compromised, none of our techniques will work. The training to visualize and create a single line of power for our technique is of paramount importance.
7) Avoiding Resistance
Aikido abhors force on force. Instead, we prefer to go around the resistance and take uke's balance away. It is worth looking not only for the connection to uke's body, but also for the places where uke resists, and learning how to go over/under/around that force. This is often a problem for people with strong bodies, who feel the temptation of ego to use strength rather than correct concept and proper technique.
Aikido techniques are designed and taught in the way they are to develop an ethical framework for the students. The techniques are done specifically to avoid injury to either partner, and ensure safety in the training. Of course this means that "as-is" the basic techniques will not be very effective for fighting. The very fact that we offer "ukemi" to uke, something no one in a real fight would ever do, shows us that the techniques are made to teach the concepts safely. The concepts, however, will be very practical when adapted and applied to a real combat situation.
The Yoshinkan techniques are not specifically to be used in combat the way they are taught as basic techniques. Jiyuwaza comes closer to the real thing, but even that is a bit theatrical (but also useful to learn stress management, body control, and dynamic movement.).
The key is in viewing each technique as a lab to practice all of the above. In doing so, we are exploring the concepts and programming the body to respond correctly no matter what we actually do in a fight.
There is a magic moment where Danny Larusso, the Karate Kid, is frustrated with doing chores he thinks have no fighting application. Then, Miyagi shows him that through those simple chores, unconsciously, he has been learning karate. It is a revelation for him - and should be a revelation for us. True aikido is effortless and natural, and comes from years of training in the techniques, each of which is designed to help us safely learn the fundamental aspects of combat which can be applied to any combat art or combat situation using any technique, aikido or otherwise.
So, in summary, do not expect to be a "badass" through your study of aikido. Do expect to learn a lot about yourself and others, and to form a foundation for any other combat art you will ever study.