Anne Marie writes, "..they were able to know what techniques we were doing because we used the Japanese terminology." This reflects what a number of people wrote. I don't understand it. I have never seen a class where the teacher gets up and says, "Everybody, do shihonage," without demonstrating. And I hope I never do.
There is an unlimited range of the use of the Japanese terminology other than the sensei demonstrating the technique in front of the class. Sometimes you get a confused partner, or they forget which technique your doing, or which attack, or you want to train with them after class, or you want to ask them what they did, or your sensei will call out techniques such as during randori or jiyuwaza, etc.
I should have made myself more clear. In my four years of aikido training in south florida, I have had personal experiences where using the Japanese terminology was helpful. I fortunately train under a wonderful sensei and at an excellent dojo where folks come to visit our dojo during their vacations, and sometimes these folks don't speak English. The Japanese terms certainly helps in communicating what is happening on the mat. Think about it: Your not sure if it was ura/ tenkan or omote/ irimi. You ask your non-english speaking partner -- ura? omote? Another example your partner is not sure about the attack -- you say "yokomenuchi" etc.
The best example was when Masafumi(sp?) Sensei from Venezuela came to our dojo for a seminar. Well, he brought a few of his students with him. They spoke mostly Spanish, and I only spoke English, the one common language that we had between us all was Japanese. Sometimes it was hard for Masafumi Sensei to convey an idea because of the language barrier, but he would try his best to include Japanese terms so that we could better understand the point he was making. (although he did have a translator). Using the Japanese terms helped him convey his point and sometimes he wouldn't have to use the translator and just say the Japanese term.