Connecting ESC's - Connect all Power wires to pins or just one?

I am hooking up my ESC’s to my Pixhawk1 and looking at the official documentation, it says to hook up all three wires (+,-,signal) to the servo rail of the Pixhawk. This is how my octopter came when I got it in pieces, seems right, but… In a YouTube video from someone I think knows what he’s talking about (, he says to only install one of the red wires to a power pin on the Pixhawk’s servo rail. Which is correct? Why the difference of opinion?

I’m also wondering How long can these ESC wires be? Can I make them plenty long for lots of room to work with?

To answer my own question: It depends on what type of BEC’s the motors use. For linear ESC’s (as in the s1000) you can connect the 5v power wire to the Pixhawk rail.