I've wondered for a bit if Barranca Hill is one of those examples of picking the route too fast. As far as I can tell (comparing engine ratings, mostly) the ruling grade Eastbound on the La Madera branch seems to have been a hair less than 2% (engines are rated 10 tons or so more than on sections like Bocea Hill) and looking at topo maps it weems to me that a line down the Ojo Caliente to the Chama at between 1% & 2% max would have been possible, so maybe Palmer's boys located a touch too fast? Or were just in love with a shorter distance...
hank