I agree.

First of all, though, the rider must have his or her saddle in a proper relationship to the pedals.

With the right saddle postion, pedalling itself holds up the torso.

For riding on the street, and not on the track, one will find that a saddle/pedal/handlebar relationship, in which one COULD lift his hands off the handlebar while pedalling, with only a minor effort required to hold the torso in place, represents the ideal position.

If one wants to know what that position looks like, starting from a standing position with the bare or stockinged feet pedal width apart, one should sit on a hard chair on a hard floor, and then, bending forward and placing the hands and arms in front for balance, begin to stand again; at the moment one's bottom breaks contact with the seat, notice the angle of the torso, and also note that one can hold this position indefinitely.