Bruce Bookman Sensei:

"The striking attacks in aikido such as shomeuchi, yokomenuchi and tsuki come from Japanese sword traditions. These types of attacks are classical in nature and when practiced with commitment and intent build strong conditioning, timing, responsiveness and most importantly enhance the kokyu-ryoku, the vital life force energy of both uke and nage. It is a good idea to train one's skills at these attacks, however, it's important to keep in mind that the classical aikido attacks have been adapted from swordsmanship and reflect an ancient paradigm of the samurai who fought on the battlefields of feudal Japan. How they trained and fought were influenced by bushido, the ancient Japanese code of chivalry. The type of attack that one may encounter today, in a dark alley is very different. This leaves the aikido practitioner the task of spontaneously adapting their classical training to the situation at hand. It is of course possible but it takes a very talented person to be able to connect the dots in the heat of the moment."

"Bruce Bookman's response to Stan Pranin's article"
http://www.aikidojournal.com/forums/viewtopic.php?p=87464#87464