He agrees that you couldn't possibly manually up-shift better than the PCM at WOT due to the valve body being electronically controlled.
Up shifts during normal driving will increase the longevity of the transmission; like preventing skip shifts, 2 to 4 with respect to throttle position.
More accurate down shifts can be achieved with the ratchet.
I think it looks absolutely ridiculous but it makes sense - mechanically. You need to be driving a '70 Chevelle for that to be aesthetically pleasing.