We’ve only rarely had folks to sled pull training for Denali. Hundreds of folks have used our 24 expedition plan to prep successfully for training and it does not have any sled pulling in it. We’ve never heard anyone complain that they wish they’d done some or more sled training.
If you feel like you need to in order to feel prepared, you can add it in. Do this by including short ME-style sled pulls in the final weeks. This will mean substituting these in for some of the weighted ME uphill hikes.
The sleds have very little resistance on the snow and so are pretty easy to pull. It’s the weight on your back that seems to take the biggest toll.