Maybe something we forget is that manufacturers are selling a product, so they'll try to present that product in the best light possible. Perhaps because of this manufacturers have something in addition to pressure issues to consider? Things like "clean burning" powder may influence the vendor far more than pressure issues exclusively perhaps.
The point being that as shooters we look at performance exclusively, vendors have other things to think about as well.
Allan Quatermain: “Automatic rifles. Who in God's name has automatic rifles”?
Elderly Hunter: “That's dashed unsporting. Probably Belgium.”