Back to the comment on being Ignorant. The word ignorant mwans one does not know said knowledge, so if one says that lifting wieghts is bad for martial arts, that is due to being ignorant of the facts.
ANYTHING that makes you strong is good for martial arts. now, Some things are better than others. For example, the body builder does get stronger, but he’s not going to be as strong as the guy doing weights for strength training., so the Strength training is “Better” for martial arts then Body building, but both are better than not doing anything.
As for getting tight, in extreme cases, especially with body builders that does happen, BUT those are guys who lift heavy, often and do nothing else. A martial artist literally does not have the time to lift that much. Also, martial arts is full of flexibility increasing activities, from forms, to stretching, and various other range of motion exercises. It woould be vertually impossible for a dedicated martial artists to get tight lifting wieghts.
Now, it is also Proven scientifically that anything that develops the muscles, also develops the joints (So long as you are not over training). So the comments that weightlifters have weak joints is untrue. In some cases if they are obssesive about body sculpting, thier joints may be tight, and more suseptible to joint locks, but it would take an extremely dedicate regime focused ONLY on lifting over a long period of time to develop that. You wouldn’t have time for martial arts in that case. And if you did do that, your joints would become much stronger, just as your muscles and bones do. Also, Raw strength helps one to resist against joint locks as well. It’s MUCH harder to get a joint into the rigth positin for aaa lock on a strong person who is resisting heavily, than a weak one who does not have the strength to do so.
The other thing to think about. if you are faced with strength of muscle, and you plan to attack the joints, wouldn’t someone who is muscualrly weak be even easier to attack the joints? The answer is of course yes. Why? Because the guy who has done weigth training has much stronger joints than the guy who didn’t, and if HIS joints are attackable, then the weaker persons are even more so.