Yes, actually I drive a Coach at work. When I was using iGO about 15years ago for my Coach driving I had ftr with hnr to make Coach options.
Never noticed any eco effects there, it was still in average 23.5L/100km.
Even on ordinary daily routes which happened few times a week. It does the job brilliant to avoid all bridges and small roads, but never found eco routes, still I was shifting gearbox same way regardless hnr.