These powders are for experienced reloaders, who know how to read pressure signs, have a chronograph, and don't want to get the absolute max velocity out of their guns.
I am an experienced reloader, I know how to read signs of overpressure, I have a chronograph or two, and I don't care to get maximum velocity from my loads.
I know that there is no RELIABLE way to know when you have reached a specific pressure by "reading" the signs of pressure.
I know that measuring the velocity of a load says nothing about pressure levels - variations in barrels, and other components can make the velocity vary widely between two guns at the same pressure.
I know it is far too easy to get loads that produce well over maximum pressures without any signs of the pressure levels that are present.
Tested and verified loads are necessary to good reloading practices. I rarely have any signs of excessive pressure even at maximum load levels. I load for accuracy and usually find it before I hit maximum listed loads. If I haven't found it by the time i reach maximum listed loads then I know that powder doesn't work with that particular load. If I didn't have a max listing then I would continue until signs of excessive pressure were present - and that could mean that I was 20000 to 30000 psi over the suggested limits for my guns.
It has been shown too many times that there is no reliable indicator of pressure until you go well beyond SAAMI specs.
I admit that I am a conservative loader - I haven't always been but I have learned my lessons and my limitations.