I have no such powder. I choose the best performing powder for each of the several cartridge I load for and rarely use the same powder in more than a couple.
+1, same here. I really believe one of the biggest mistakes a reloader can make is using the wrong burn rate powder. If the concern is that unused powder will go to waste, it just doesn't make sense.
First of all - powder that is properly stored has a very long shelf life. Second - the cost of the bullet is the most significant cost of reloading a round, and to use a powder that is poorly suited for the load you are developing will not yield the best results.
But hey, everyone is free to make their own decisions and live with the results.