Different studies have suggested different results, but the vast majority I have read have all stated that the 800 is over 50% anaerobic. I'm completely willing to accept that this will vary for different people and any program needs to take into account each individual's specific needs.
So for that reason I whilst I think aerobic work is important, I think that training the anearobic system is slightly more important (but obviously you need both in a good program). Correct me if I've misread your comment, but I read it as saying that cutting back on aerobic work is a "shortcut". If you are replacing it with a lactic tolerence session, which if you have enough speed to do properly will hurt a hell of a lot more than a tempo or long steady, is most definately not a shortcut. I feel many athletes who neglect speedwork are often unable to do the lactic tolerence sessions at sufficient speed to reap the benefits (eg the athlete that can run a flat out 300, then 1 minute later run the same time - that's not because they are fit, it's because they are slow!)
Obviously if the 800 athlete sees themself as a miler also the aerobic content of their training needs to be higher to reflect their ambitions over the longer event.
Also, remember some studies have shown the 100 to be around 10% aerobic, and Kratochvilova ran the world record off 200m training (doping or not, that's the training that worked) - something to consider when addressing the quantity of aerobic training needed for the 800.