They're right... so long as they're talking about skidding on south Puget Sound glacial outwash soils made entirely of cobbles the size of golf balls, where it's too flat to get any lift with a yarder, and soil compaction is impossible. 'Course, the only place where logging like that is done is right where I work. Twenty miles in any direction and you're back in hill country where a yarder is the most sensible tool.
Shhhhhhh. Don't confuse them. If one of the 'ologists read your post, it would be edited and used to prove their point for all types of ground.
Like when I was told by one, that if subsoiling pops the roots of leave trees, that it was my fault for allowing skid trails to be too close to leave trees. We're talking SW Warshington, with tree spacings of 13 to 28 feet AFTER cutting. OOOps, soapbox needs taking away again......my bad.