Overall, I sort of understood the physics explanations. It has been a little while since I have taken math. The last two sections were pretty difficult for me, especially as I do not know what gearing is. I have no experience with rowing so I had a hard time visualizing these things, such as balance and force differences for speed (ie pulling hard or pulling weaker). Some concrete questions I had are about some terms: What is slippage? A button? Gearing?