I learned that some wonderful person/organization actually grooms the New Boston Rail Trail for cross-country skiing!
Caren and I went as a lunch break, happy that at least one other skier had laid down tracks ahead of us, but when we met up with him near the official trailhead, he told us that someone from New Boston (Parks & Rec?) was grooming the trail ahead. Sure enough, there was a snowmobile (usually none are allowed) doing multiple passes, dragging a thing that grooming laid down an surface from skiing heaven!