how is allowing someone to double grade because they are a dan grade of another style, any different a privilege than allowing them to wear their black belt.
if u have graded to black belt level in a recognised association, u should be allowed to wear it in similar styled clubs.
ie) a black belt in shotokan should be allowed to wear a black belt whilst training in a wado-ryu club, as they are similar, both are styles of karate. they should however, wear the appropriate belt during gradings.
but there is no point a shotokan dan grade wearing a black belt if training at a kung-fu class.
in the outside world, if u attained a doctorite in phsics, u are allowed to put Dr in front of your name when filling out any document. if u then went on to learn sociology, u are not asked to stop calling yourself Dr because it is in a different topic.
it is nice to see a dan grade humbly put on a white belt voluntarily when visiting another styled club, but it should never be demanded of them.
a few years ago, i had an unfortunate meeting with a goju-ryu '2nd dan',
for 2 years i allowed them to train in my club, and start grading again from white belt, although still allowing them to train wearing their black belt.
this person had not trained in 5 years in goju ryu, so i didn't expect to see a great deal of flexibility or crispness in techniques. as goju-ryu is a very different style of karate, i accepted this person would not now our katas. however, alarm bells did ring in my head, when i was having to teach all basic techniques that are on the 8th kyu grading (front punch, reverse punch, front kick, roundhouse kick, side snap kick). it was also quite worrying, when after 3 months of doing these techniques, they were still no better than the first night they learned them.
now, i believe anyone who attains a 2nd dan in any style, no matter the length of time not training, after 6 months of training twice a week for 2 hrs, some memories will have been jogged. something would be remembered.
but no.
each time they went for their gradings, this person got the lowest possible marks to still pass, but back at the club, there was no desire to improve on the skill. after nearly 2 years of training, this person had reached a skill level that i expected at 6th kyu, but they were now 4th kyu. several times during training, this person had demostrated little outbursts against other students, that no dan grade would ever do. this was the last straw, i removed them from my club, and demanded them to bring me details of where they had previously graded, and under what association, or they no longer had the right to wear their black belt in my club again.
the next training session, this person turned up rather sheepishly at my club, ready armed with an appology, but no proof of her rank. no certificate, no licence, no details of association. just the name of the club that shut down 5 years before they came to mine.
unlucky ! i happened to know this club, and its old instructer, who had 'retired' from martial arts, a bit of an oddball he was, but he did have many pearls of wisdom for karate. i rang him up, and wasn't too supprise that he did remeber my problem student. her personality was unforgetable. he gave me the details of the association he was with. i rang them, and this lady had only ever attained 4th kyu with them in goju-ryu. i then rang several other karate associations in the uk. no-one had heard of her.
suffice to say, she was removed from the club !
i would like to add that i, in no way, think that goju-ryu karateka are crap, because of my run-in with this fake. i respect their ability and style.
i still will allow people to wear a black belt from another style whilst training with me, but i will revoke this if they show signs of not being of dan-grade quality / knowledge.
if u ever have to teach another black-belt in a similar style, more than u would a beginner, ring the alarm bells.