They use our airport [KPOC, La Verne, CA] for controller training a lot. This past Sat AM - I got this whole long clearance from the controller . .. "90P, fly runway heading, I'll call your turn, no turns before the freeway, maintain 2500 or below, noise abatement turn requested." I sat there waiting for the take off clearance that never came. I was about to push the button and I heard him call out: "90, cancel take off clearance," I said: "I never got one, thats why I'm sitting here. Holding short" That flustered the hell out him. There was another airplane on downwind - about the turn to base. "90P, can you do an immediate departure?" Absolutely. "90P, cleared for take off runway 26 left." "Cleared for take off 26L, still need the restrictions?" as I'm rolling. Dead silence. 10 seconds later one of the voices I recognize comes on and says: "90P, no restrictions for take off, contact Socal Approach upon reaching 1700". It's not just us that get confused in aviation. After we took off, my wife chimed in with: "He never cleared you to take off the first time." Good to know.