I always found it interesting that they chose to call this school of magic "evocation". To evoke something is to call it up, to allude to it, to summon it. If you look it up on Wikipedia you get an article about conjuring demons. But if that's what they'd called "conjuration" they wouldn't have had a name for evocation. There's not a better word that describes it.
Evocation's tricky like that. It has no historical precedent. People, at least in Europe, who have actually believed in magicians believed that they could fly vast distances and turn invisible and bind spirits to their will. Fireballs don't come up. The word fireball, in the sense of a shooting star, dates back to the sixteenth century. The idea that you might throw a shooting star at somebody seems like a modern invention, as is the now-classic elemental trinity of fire, lightning and ice. It only exists because video games demand some way in which magic can be made to function the same way as a sword does. This wasn't a need people in the sixteenth century had. Magic was often a power fantasy - see Dr. Faustus - but they never imagined it as having a military function. Probably because, as we've said, they actually believed in magic, and it's much easier to believe that somebody can turn invisible than it is to believe that they can shoot lightning from their fingertips. After all, if they could do the latter they would rule the world, and they evidently don't. The closest we probably come is something like Prospero evoking a storm to wreck the Duke's ship, which makes sense because storms happen on their own all the time anyway. They appeared to think that you need some sort of intermediary agency, a spirit or a devil, to work magic. The idea that energy could just come straight from the air, channelled by the will alone, seems to be a product of the modern era.
What this means is that we have an idea of what a society with curses, witches, etc. in it might look like. We have records of people who actually believed they lived in such a society. We don't have an idea of what a society where certain people can set things on fire just by looking at them would be like.
Off the top of my head it seems that evokers, unlike more academic wizards, would be much more rough-and-ready, less absent-minded, more direct and used to thinking of themselves as tools. They would take service in the armies of the emperor or hire themselves out as mercenaries to local lords. Say you're a thane at war with the thane in the next glen over and a guy who can cast Magic Missile four times a day comes to town. How much would his services be worth to you? What kind of bidding war would result? What would you do if you got outbid? Remember, every day he can kill two or three people of his choice, basically freely, before he has to lie down. And what's that guy's life like, wandering around doing a new one of these every week? Why did he choose to specialize in a school the only practical application of which is to kill people?
Anyway I still don't quite know how this is a post.