I would get another opinion, my 141 school did not teach this. They only taught to hold full aft whenever taxiing/takeoff on soft fields, and short field takeoff.
Just because the instructor told you doesn't mean it's right... I was taught a wrong procedure before, and have heard of egregious stuff not taught like not leaning at altitude, etc.
From AFH 2-19 to 2-20:
When taxiing at appropriate speeds in no-wind conditions, the aileron
and elevator control surfaces have little or no effect on directional
control of the airplane. These controls should not be considered
steering devices and should be held in a neutral position.
When taxiing with a quartering headwind, the wing on the upwind side
(the side that the wind is coming from) tends to be lifted by the
wind unless the aileron control is held in that direction (upwind
aileron UP). Moving the aileron into the UP position reduces the
effect of the wind striking that wing, thus reducing the lifting
action. This control movement also causes the downwind aileron to be
placed in the DOWN position, thus a small amount of lift and drag on
the downwind wing, further reducing the tendency of the upwind wing
to rise. [Figure 2-15]
When taxiing with a quartering tailwind, the elevator should be held
in the DOWN position, and the upwind aileron, DOWN. Since the wind is
striking the airplane from behind, these control positions reduce the
tendency of the wind to get under the tail and the wing and to nose
the airplane over. The application of these crosswind taxi corrections
helps to minimize the weathervaning tendency and ultimately results
in easier steering. [Figure 2-15]
The presence of moderate to strong headwinds and/or a strong propeller
slipstream creates lift on the horizontal tail surfaces and makes it
necessary to control the pitch attitude while taxiing. The elevator
control in nosewheel-type airplanes should be held in the neutral
position, while in tailwheel-type airplanes, it should be held in the
full aft position to hold the tail down unless the headwind gets very
strong, which allows for an elevator position closer to neutral.