FS/FT: 2 Firepods/HP 4/Power Conditioner in a Rack

I've been using speaker cable for my monitors forever. AFAIK you only need a standard 1/4" cable to do connections from monitor to interface L/R outs. There is only a TS connection here (correct me if I am mistaken).

I've been running speaker cable (TS only) from my Fireface 800 outs to my Central Station and also from my Central Dtation outs to my headphone amp. I've never had a problem or any degradation in the signal...? Why is this a problem?
 
I know that this statement is true^ I switched to TRS today and heard no noticable difference, but I suppose it can't hurt to stick with it!