Seriously, learn a technique to use it, not to be able to claim to know it.

So how do you propose learning something you know nothing about? If I didn't know what Object-oriented programming is, how would I learn that it's useful to me? You need to constantly evaluate new ideas whether or not they end up being useful. Any other approach results in a self-fulfilling prophecy of ignorance.

I never meant to suggest that one should not constantly evaluate new ideas. Indeed I do try to constantly evaluate new ideas.

However I am constantly trying to integrate those ideas into my knowledge and life rather than learning them as stand-alone things. Sometimes that doesn't work - some ideas really can't be fit into any framework that I have. But usually it does, and usually the fact that it is not sitting in a vacuum allows me to ask better questions, learn faster, and make use of what I have learned more quickly. And since it does that for me, I sometimes tell other people that it is a good way to try to work as well...