Complex sentence: Although slope gradient is the primary consideration in assigning a trail difficulty rating, other factors come into play--such as: width of the trail, sharpest turns, terrain roughness, and whether the resort regularly grooms the trail.
Split into simpler sentences: Although slope gradient is the primary consideration in assigning a trail difficulty rating, other factors come into play. Also considered: width of the trail, sharpest turns, terrain roughness, and whether the resort regularly grooms the trail.