You say:”European shades (i.e.: IKEA) don't use harps and are supported directly by the sockets. I'm not as big of a fan of this style as their fitter doesn't work on all conventional North American sockets. They're just too specialized.”
It’s not just Europe and IKEA - the whole world makes lamps that way, ONLY the US uses harps. I guess when you’ve only used one way, you think that’s the right way, but as it’s a standard for the whole rest of the world, all fittings fit.
Wouldn’t a better description be that it’s the US, with your imperial measurements and your localised way of doing things that’s specialised?
When one country is doing something and all the others are doing something else, it’s hard to see that the rest of us are the ones walking out of step.
Perhaps, given your specialised electrical supply and specialised electrical fittings and specialised lampshade bearers, the title could be amended to American Lamp Class, or at least some provision given for other ways of doing things?
This isn’t meant as a snipe against your tutorial - i think it’s brilliantly done and extremely informative, but so much of it is only relevant to the US and Canada.
If I lived in the US, it’s the best instructional on lamp making I’ve seen. You should make an ebook!