Pitch vs power is a lot more subtle than just pushing the throttle up or pushing the stick forward to speed up; the real answer (IMHO) is "it depends on where on the L/D curve you are". At high speeds and level flight, power is the primary speed control, and unless you are flying an F-16 or Airbus, you will have to adjust your pitch (usually with trim) to compensate for the tendency to climb as speed increases. If you are slow, however, and on the backside of the L/D curve, then pitch has a much greater role in airspeed (actually, AOA) control, while power serves to adjust rate of descent or to maintain altitude, and has much less effect on speed. So on approach, you control your speed with the stick (and trim for the speed), while using power (or the dive brakes in gliders) to adjust you sink rate for the desires approach path.

From personal experience, this works in everything from 2-33s to F-15s.

"Stick and Rudder" covers it well, I believe...

Kirk
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