Not all the towers along a transmission line are identical. Look closely at a tower where the line makes a sharp turn and you will likely find it is wider and beefier than other towers along the route. The added strength and weight are needed to resist the unbalanced pull of the conductors, which might overturn an ordinary tower. These special towers are called deviation or angle towers.
The transmission-line tower everybody knows is an Erector Set latticework of steel girders and diagonal braces. The techniques for designing and building these towers are the same ones used in constructing steel bridge trusses or crane booms. The individual pieces can be made cheaply from rolled steel and then bolted together on the site. This last point is more important than it might seem: transporting a fully assembled tower 100 feet tall is an awkward and expensive business.
Even with all the features and plugins, Canvas presumes certain ways of organizing classes that might not be universal, just typical. And if (like me) you’re an atypical user, you have to choose between constantly fighting with the system or gradually doing more and more things the way Canvas wants you to do them. This, by the way, is why it’s never true to say that technologies are neutral and what matters is how you use them: every technology without exception has affordances, certain actions that it makes easy, and other actions that it makes difficult or impossible. A technology whose affordances run contrary to your convictions can rob you of your independence — and any technology deployed on the scale of Canvas will inevitably do that. It will turn every teacher into an obedient Canvas-user. I don’t want to be an obedient Canvas-user.