I did a solo in the BWCA in June with my kayak. I was much faster on the water and just as fast on every portage that I took. I single portaged with my kayak, I was ready to portage the kayak in 5 minutes or less, and I could go on big water with big waves. I believe the article was not totally researched.
Touring Kayak Paddles
Full Size Sail Rig