Now that we'er talking about "working a yard," here's my suggestion. Widen the inner loop so that it comes as close as feasible to the outer loop on the narrow connection to the two dogbone ends. Now, extend the yard lead to fit between the four mainline tracks down that narrow area and connect to the inner loop just before the turn. Voila! A long enough yard lead to build a train in the yard without fouling the mainline.
Chuck
