Vic,

What I think your friend was trying to say is that a properly balanced plane can fly slower than one that is nose heavy.
If the plane is nose heavy, the tail needs to pull downward to keep the nose up, thusly increasing the "work" that the mainwing needs to perform, either by increasing the angle of attack, or airspeed to increase lift.
Since any given wing will stall at the the same angle of attack no matter where the CG is, it becomes a matter of having to move the air over the wing faster to counteract the downward force needed by the tail pulling down trying to keep the nose up.

Bob