Without the downward pressure on the tail with up elevator, the tailwheel will not have enough pressure on it to be effective.

I wanted to put some "teeth" in this by a demo. Notice the elevator in Jim Deitrich's 50% scale Spacewalker while taxiing and when he starts the take-off roll. He holds up elevator while taxiing to keep pressure on the tailwheel. The same applies when he starts his take-off roll.

http://www.youtube.com/watch?v=5ZAXarCvVoE

Beautiful plane too