You have to already have a good working knowledge of chords and what those chord patterns look like, in order to be able to recognize what someone sitting across from you is doing - and if you have this knowledge, it is very helpful when participating in jams, etc.

The goal should be to become the very best player you can be while maximizng whatever talents and God-given abilities you might have. Whatever "tools" are required to accomplish this, are the right means to this end.

All tools are worth looking at and utilizing if you can derive direct benefit from them. If you start getting too analytical about methods, you'll end up screwing yourself one way or another. Remain open and utilize any and all possibilites. My $0.02