New knowledge to me.

[HiryuHien]

The last style of karate(okinawan from a friends father) I trained in taught me locks, grapples, strikes, ki, kicks, mental preparation, pressure points etc.
The oldstyle jujutsu seminars I have had the honor of visiting in the us and canada teaches very similar techniques and their forms are somewhat different.

But in essence its like I was doing the same thing.
I know basic principles in all MA's are the same.

It still strikes me as rather cool though that some okinawan karate, adapted by peasants which is traced through the fukien province in china and linked to white crane, is so darned similar to oldstyle jujutsu (dont know the origin) used by the samurai class. Just goes to show that principles in many cases override human divisions and differences despite some of our foolish actions as collective humankind.

later

[koto_ryu]

That's because despite what we think nowadays, many martial artists back in the day cross-trained. Take the average samurai, for instance. He knew swordsmanship, horsemanship, kyudo (archery), jujitsu, and a number of other skills and talents. Cross-training back then was a way of life, and nowadays we just think it's something new.

[HtTKar]

True,
warriors trained like monks in seeking knowledge from many different teachers in many different places and taking the best of what was offered to develope their own personal style. It took a long time to train a warrior, many many years. Personally I wouldn't call them martial artists...I would call them warriors. The elite upper class, and those destined to protect them were often the only people capable of spending that much time developing. The Samarai and Spetsnaz are examples of this.

Martial arts were developed to teach many people in a relatively short period of time how to fight in preparation of battle. In times when you didn't have many years to prepare.

Warriors would have studied all of the martial arts they had the opportunity to, and would have incoorporated the best techniques into their personal styles.

So Cross-training for the majority is a relatively new thing.