I agree that sleds are more trouble than they are worth in the Whites. One winter on our Pemi ski-through someone brought a sled, which was a major pain in Zealand Notch, not so bad on the Shoal Pond Trail, but then a nightmare on the side hilling along the upper Wilderness Trail between Stillwater and the Thoreau Falls Trail junction. "Never again" this person said.
Sleds are nice for the trips into Roaring Brook or Nesowdahunk for climbing in Baxter State Park, and even all the way into Chimney Pond if you have good ski technique for the trip back down to Roaring Brook.
Perhaps s basic first principles rule might be that if you cannot easily ski a route, a sled will be more of a curse than a blessing.