More of a gun lesson than an art lesson.
Being a massive gun enthusiast myself, I followed along the gun history and gun explanations just fine, but I can certainly understand how gun-uninformed people could get bored/confused by this... particularly bored. Considering this flash is trying to appeal to artists, and artists are not exactly notorious gun collectors, the flash loses its focus a LOT.
We don't need a history recap on the first chinese uses of gun powder for you to explain how to trace a gun... and thinking about it now, you went into VERY LITTLE detail on how to properly trace guns to make them look good like you do. For example, making radial fills work for realistic effects, how to make the muzzle flash look blurred, how many frames the muzzle flashes should remain, how to set the weapons up as independant symbols, or in segregated layer folders so that you don't end up with hundreds of layers everywhere...
Your guide basically went "Here's my work, here's the history of guns, here's how guns work, these are the different types of guns, here's a gallery of my guns, bye". There's nothing "Ultimate" about that.