I disagree with athenian200. I think INTPs do over utilize their intellects to the point of getting lost in analysing theories rather than applying them. I know that if I come across an idea or concept that interests me, I can spend a really long time gaining pleasure from dissecting it in my mind. I have very little interest in implementing the ideas in the real world.
As for whether this "knowing, but not doing" is a bad thing, I think it can be. For example, my perfect job would consist of being paid to come up with new ideas(E.G. concepts for new TV shows) while others would be responsible for making my ideas into reality. However, no such job exists. That's the problem for me.