RB Double Bass pedal curcit

Guess this probably belongs in the questions forum but oh well.

Does this make sense to anyone, cuz it sure as hell doesnt to me. Its to have 2 bass pedals going at the same time.

I guess there are ppl that have had 2 standard pedals and just put a Y jack to connect the 2, the problem was that when one pedal was down, the other one wouldnt register the hits.

So Im wondering if anyone understands this diagram and can explain it and maybe break it down Barney style for me.