Using frog juicers for polarity control


Please excuse my lack of sophistication re DCC wiring.  I am new to this blog -- thanks for letting me join -- and have found the wiring instructions in the related web site invaluable.  I am in the process of converting an older DC-wired layout to DCC operation.  I have an NEC Controller and am starting the rewiring.  

From what I have read I understand that the Tam Valley hex-juicer can be used to auto-reverse polarity on up to three separate circuits.  In each case, I understand that two connections are used on the hex-juicer, one each connected to the two track rails, with both track rails for the specific segment insulated from the rails on adjacent segments which could have different polarity.  So far so good.  And so much better than the cumbersome arrangements needed to operate in DC.

I also understand that for non-reversing segments, such as a siding, a single wire from the hex-juicer (or from a single juicer) can be connected to one track rail, which is isolated on the siding side of the switch from the rail on the mainline side of the switch; but the other rail on the siding side of the switch need not be electrically isolated.  Is that correct?  

As the layout is currently designed, I can reverse train direction in both directions around the layout, or in simplest mode simply run a train in a figure eight in either direction (without changing any switches).

In addition to the hex-juicer, would you recommend circuit breakers  for each segment?  If so, where I have 4 reversing segments (both track rails isolated and wires to both track rails from the juicer(s)), plus two sidings (with only one track rail isolated), do I need 6 circuit breakers?  Or just 4?  

I have not gotten to the issue of actual control of the switches (until the basic wiring is resolved I'll be throwing switches manually and operating only one engine at a time), but would appreciate any recommendations you might have for switch control.  

Thanks again for any insight.
Bill Demarest