ive been of the bash for a while,and i am like new right now.
what is the most effective fighting technique.

1-start out relax and stay relaxed through all the poses
2-start out relaxed and build into hold
3-start out on hold and stay in hold

It depends what you wan to achieve. For fluidness and style if you were making, say, a free running video, you'd use lots of relax. If you are just starting out, I recommend using the hold technique and slowly experiment outwards with relax added in.

Exactly, that's best way to practice.

Also, you can try -30 gravity. It is good for realistic movements and is near to real life gravity.

A mix of extended/contracted and relax joints can be very fluid, and can build momentum for a powerful attack. It takes time and training, but you'll catch on.

In 9.28 grav (aka default) best to start relaxed and keep the relax until the finishing frame then hold (Press C) or just keep the forces applied.

In -30, Try to look at Videos of People fighting IRL and try to imitate them.
DO NOT PRESS C at the ending frame.
The gravity is enough to break the pose and end up getting an ugly pose.
So keep the forces applied to keep the pose stable.