The misleading term 'on the step' is just a way of saying that you have reached the max level cruise speed for the power setting.
If you set the cruise power setting on reaching the cruise altitude the aircraft WILL accelerate to this speed.
You can reach this speed quicker by maintaing the climb power and accelerating to a higher speed and decelerating.
When all the forces are balanced out the result will be the same, all things being equal.
There's no mystery.