Yes, it's possible to bring down the wall so that you're in the timeless and egoless state that K describes, but can also think whenever you need to, and then stop thinking. In ordinary life, thinking gets out of control.

I have doubts that the usual methods of meditation actually do this. They're healthy exercises that help you relax and clear your mind, largely because of all the deep breathing, but the premeditation and practicing shouldn't be necessary for a mystical experience.