This trail is not really a loop, it is an inverted Y (or Greek lambda) shape. The left leg is the original Erie Canal route, and is not finished well. The right leg is mostly finished in stone dust, though it has a couple of jogs around business parking/loading areas. The top section is mostly mowed double track. It is in the Town of Brighton, the rest is in Pittsford.
The left, right and top sections aren't connected as trail, you have to use short sections of a busy road and/or business parking lots. This connection is not well marked. You can make a loop out of the left and right sections by taking the Erie Canal Trail (paved here) between the southern ends.
I now commute to work from Pittsford to Rochester on the right and upper legs. The right leg is ok in most weather, though it is unplowed and a hard ride in snow. The upper part is not good to use in wet weather, it gets soggy wet.
I wish the town of Brighton would finish the upper part, their part of this trail. It could be a good link between residential areas, the southeast part of Rochester and the Pittsford Plaza area. Like most places, trail development does not consider utility cycling, only recreational use. This section is fine for walking and MTB use in good weather, but not on hybrid or road tires, especially in the rain.