Lots of people get confused easily especially when it comes to fast twist slow twist heavy bullets slow bullets light bullets fast bullets.....
They even get really confused when it comes to slow burning powders fast burning powders especially when generally slow burning make faster velocities and fast burning powders make slower velocities if you use an appropriate size cases. And unless they're not talking about high pressures and low pressures with high speeds and slow speeds LOL
Ignore all that stuff and shoot a few groups. If the bullets go into a reasonable perimeter, it's "damn the torpedos- full speed ahead!".
The rest is just politics. :
That means it's too confusing for my poor brain, so I just don't deal with it. Ignorance CAN be bliss.