The one pound powder can is a trial size container.
Most new powders do pretty much the same as old powders. Mostly you have to burn a significant amount of powder working up loads to match what your preferred powder does, then burn more to see if there is any improvement.
Sometimes a reduction in group size with a new powder is a result of practice and personal improvement coupled with care and attention to shooting technique when working up a load.
Sometimes when one does a side by side comparison of the best load you were using in the past with your newly discovered "most accurate load", the old load is just as accurate.