The willy wodger replaces a flimsy stamped mild steel hanger which was bolted on using the QR pin on the stoker's seatpost clamp. The cable routing on the old hanger was 'dramatic'. The willy wodger is stiffer and sits lower on the bike (still high enough for a suitable straddle cable and some cable travel) so that the cable outer is shorter and straighter. I can still attach carriers etc. It cost a bit more than I had anticipated, but overall it was still cheaper than new paint on the back of the bike and a braze-on hanger which measures were contemplated if Quantum had needed to melt the old rusted-in seatpost to get it out.
I am in sync with you on the hanger. Can you provide a source for them?