When training 800m runners, I like to get hard mileage in first, then go directly to speed/power and then work on special endurance II and speed endurance, some like to work both ends towards the middle. I know others to the detriment of their runners go strictly long too short and they usually over race their kids. Mike, I, and others don't always agree, but I am glad you feel like your learning something. I am big stickler for general fitness no matter what race you compete, because to be a champion means you don't have time in season to worry about fitness levels.
I usually end up racing my 800m runners in 200's and 400s early on in my high school season. I try to stay away from the 800-1600 trap although I may stay away too much, but I'd rather find that 800m runner who is willing to go out run the 3200m and come back and do the 400m and 4×4 as well in early season meets.
Every workout should have 1 purpose and all the training units should be built around that purpose. That workout should fit into the microcycle, that microcycle should fit the mesocycle, and so on. Your speed/power mesocycle should have some endurance qualities to it, both aerobic and muscular, but that should be nothing like your base or general prep work. That said your GPP and SPP should both have some sort of max V and accel work in it.