The parent poster didn't suggest otherwise. Thanks for making me aware that the author is a prof! But I'm afraid that makes things even worse. As I see it, the

The parent poster didn't suggest otherwise. Thanks for making me aware that the author is a prof! But I'm afraid that makes things even worse. As I see it, the writing quality is barely acceptable for an intern: it's so colloquial it almost buries the core message, and it's full of very irrelevant details. Two examples: (1) We're talking about straight vertical lifting from the start, so why bother giving the formula that considers the angle of the force vector? (2) why analyze the energy flow of stacking barrels when the most straightforward implementation (as discussed later) deals with simply lifting barrels some height above ground level? This article could have been more clear and more approachable after editing it down to half the text.