Practically anything may be practiced in patterns. Patterns are the history books of the martial arts. They memorialize the roots of the arts and help carry on the traditions of the arts. Most of the techniques used in patterns are old and outdated for use in modern day fighting, but they preserve the history of the arts. We may learn from history but that does not make what was taught in the past correct, nor does it make it relevant in modern times. Since patterns are more of a mental exercise than a physical one, performing patterns of any style and using the techniques of that style will aid your development in your style, since you are learning to concentrate and use precise muscular control. In my experience, students who do well in patterns are usually effective fighters, but effective fighters do not necessarily do well in patterns. However, this does not mean that the techniques used in patterns have any relevance to actual modern day fighting. There is the way things are performed in patterns, and then there is the way they are performed in fighting. The pattern performance and sparring are two different entities, so they do not inter with each other. If you are proficient at driving a motorcycle, it does not interfere with you ability to drive a car.
I had good parents so did their best at raising me. That does not mean they did not make mistakes, but I knew that, no matter the outcome, that they were always doing what they thought was best for me. Most martial arts are doing their best at teaching students the right thing to do. They make mistakes, but, if they have good intentions, they will see their mistakes and correct them. I am a loyal student of Taekwondo, but I am not enamored with its mystic. If it is wrong in its teachings, I tell my students why. If other arts are wrong in their teachings, I tell them why. As stated above, no one really care what an art does in its patterns, but if they are wrong in their fighting or self-defense teachings, then they need to change.
If you practice any technique enough, you may become proficient at it and it may get the job done, but that does not make the technique the most effective and efficient way to get the job done. A well trained ballet dancer using ballet kicks will probably win a fight against a lesser trained fighter in Taekwondo. An example of a practically useless technique used in fighting is the boxing bolo punch, which is an upper cut performed in a large circular motion.