I've been criticized to death for my strict policy of loading shotgun according to published recipes.
Just because the wrong wad will work ok 1k times, doesn't mean it's a safe option. Those who take shot shell loading with a grain of salt, are just asking for a lesson in physics. And just because it will go bang, doesn't mean pressures aren't going sky high on some. Reading pressures on a shotgun shell is about like trying to check the tire pressure on a big rig by pressing your finger into it, in other words, it just doesn't work.
And just because Mec says a #32 powder bushing will drop X number of grains of a specific powder, does not mean it is. To date, I've never had one single powder bushing that was dropping even close to the recipe charge. So IMHO, it's absolutely, positively necessary to check all bushings against a scale to make sure they are throwing a charge within reasonable weight variations.
GS