Black belts in multiple arts in a short time
What originally spawned this post was some research on the Bujinkan, discussed here.
A lot of the time here on Bullshido, we come across an individual who's resume reads like a Black pelt grocery list:
6th Dan Shotokan Karate
4rd Dan Okinowan Karate
3rd Dan Judo
3rd Dan Japanese Jujitsu
A lot of times, this is an alarm bell for starting a bullshido investigation. Normally this is coupled with some other fact, like the person has only been in martial arts as a whole for 8 years or so.
However, what is the feeling on persons who obtain multiple belts in arts that are very similar? For example, if someone studies a particular ryu of Karate, and attains 3rd Dan, wouldn't it be easy for them to transition to another Karate, and even attain rank quickly, due to already having thorough understanding of the basics. Granted, there may be different katas to learn, and a handful of theories particular to the art, but aside from that, there shouldn't be much else. I would assume that this would hold true for combinations of Judo/Jujitsu, Akido/Akijutsu, BJJ/GJJ, etc.