Re: should there be an age for black belts?
as to practice with differing ranks... i LOVE working with rank beginner's their reactions are genuine, and with lower ranks your waza gets tweaked by slower more precise practice... I don't PREPARE for tests, i practice the same all the time... I chose as Uke for a test someone who is usually LARGER, STONGER, and WILLING to be treated a little roughly (not for the whole test!!!) so that I can really "PUT IT ON" and challenge myself... when i am uke for a test i tell the nage to not hold back, don't BREAK me, but a few bruises are okay... in my dojo we practice all ranks mixed and there is no advanced or beginners classes... just everyone together in all classes