Pioneer 1-2-3 Channel Amp bridging

From what I can see from your post, your wanting to use a 2 channel amp in stereo and bridged (tri-way) mode.  You need to use a passive crossover network since you aren't going to be able to utilize the amplifiers crossover .  Crossover design is definately not for beginners (and even some pro's), but you can buy a crossover module to simplify things.  

        As far as your diagram goes, it is probably showing your satallites wired in stereo, and your sub wired to the + terminal of one channel and the - terminal of the other, with the capacitors wired inline with 1 wire of each satallite and the inductor wired inline with the sub.  If you purchase a crossover module, all you will have to do is wire 4 wires from the crossover (L+,L-,R+,R-) to the amp, and the other 6 to your speakers (2 for L, 2 for R, 2 for sub.)  If your satellites are beefy enough, another option would be to run them full range and buy just an inductive coil for the sub.  If you don't like the idea of any of this, just e-mail me ( jellynutzo@aol.com) and I can help you design a crossover.