Per another topic floating around here on Barrel Life, and going back to the day,
A lot of the horror stories with the 6.5-284 and barrel life came from the days when the load was built using the fastest burning powder you could find, stuffed into the case at max capacity, and shot on the ragged edge of blowing it all apart. The shooters were knowingly sacrificing barrel life for max velocity/performance, but that got "lost in translation" in a lot of cases.
Fast forward to today, and shooters are figuring out that by keeping the pressures as low as they can, especially the initial spike, by using slower burning powders they are not burning out the throats as quickly.
The key for the slower burning powders is having the barrel length to optimize the burn and keep the velocity up. The other key is also the case design, with the shorter / fatter designs like the SAUM, having an advantage over the longer / skinnier designs like a typical magnum.
I learned back in the day when I was legally making pipe bombs with smokeless powder and blowing things up that there was an optimal balance between the length and diameter of the pipe to get the optimal powder burn/explosion. Too short & fat or too long & skinny, and we would always find more unburned powder in the post blast analysis. A good balance between length & diameter, and we would find very little unburned powder.
While some folks are seeing the performance of the SAUM as being magical, IMHO it is just that optimal balance in case design that allows very efficient burning of a slower powder charge, which when coupled with a longer barrel, means that you get good velocity results with out an excessively high pressure spike at the beginning (which is what ultimately kills barrels).
I am running a straight .284 with a .30" barrel, and I am going to start looking at some loads based off of some slower burning powders like H1000. IMHO, the .284 case design is a little on the skinny/long side, so I don't think that it is going to be optimal, but it just may be good enough coupled with the longer barrel.
Sorry for the sidetrack, but thanks to the OP for sharing, hopefully as more discussion takes place on this topic, we can all figure out an optimal combination of case, powder, and barrel (maybe also bullet) that will allow good velocity without the total loss of barrel life.