We use this phrase in Yoseikan too. I have always been taught, and as a result teach, that it means "please show/teach me." It is said by both individuals (senior and junior) because both can offer a teaching experience to the other. Obviously, the senior can teach the "technique" to the junior. However, (I think this is sometimes overlooked) the junior can provide the senior a new way to learn how to teach the technique. There are people that have limitations (skill, age, physical handicaps, etc.) where the technique must be taught a little differently than the "traditional" way. Simply said it is (should be at least) a reciprocal relationship. At the end of training we add the formal Japanese "thank you" for the same reasons - thank you for what you have just showed/taught me.