Jeet Kune Do is not a style. Jeet Kune Do is application of techniques that work best for you in practical self defence/fighting, no matter what style it is pulled from. No one martial arts technique or system is more superior to the other - these are merely just various 'disciplines' that you can encounter and 'develop' yourself in, whether it is striking orientated (Taekwondo, Karate, Boxing), Grappling (Hapkido, Aikido), Weapons (Escrima, Kendo) - these arts benefit you in different ways.
It doesn't matter whether you want to fight in competition, learn self defence, or merely just be motivated for General fitness - the art doesnt make the fighter - its what the fighter makes of the art
Bruce Lee revolutionized martial arts in his concept of 'Jeet Kune Do', which once again, is not a style, but rather, it is Bruce Lee's personal philosophy of martial arts. He researched, took methods and elements of various styles and disciplines, and adapted them into a practical self defence system that worked for him. The philosophy and ideals of 'Jeet Kune Do' though are expired, because it was Bruce Lee's personal vision, and sadly 'Jeet Kune Do' now is merely an archive of Bruce Lee's research of martial arts, because he is no longer with us to progress it further.
But the idea, the philosophy behind 'Jeet Kune Do' is what all serious martial artists should consider. It doesn't mean you should cross train in multiple styles for the sake of expanding your knowledge, but rather, you should not be biased to your chosen style and criticise others - martial arts has created endless horizons for people of different cultures and backgrounds to share their knowledge and grow - so you should always keep an open mind to other arts.
Bruce Lee was known to strongly oppose the practical element of Karate in fighting - but regardless, he spent alot of time researching the art anyway, learning the techniques and their applications.
I encourage all here who are interest in martial arts to continue to expand your horizons and educate yourself. Your growth in martial arts should never be limited by your chosen formal tuition in a particular style - you should always be open minded and take the time to research and learn of different styles, methods and techniques. That is the essence of martial arts.
Regards,
Ben.