You are absolutely correct sir. Same goes for whomever is cutting said shafts... and whomever is selecting the spine of said shaft for a particular bow.

You take any model bow... with any model arrow.... and as long as the system is the same every time.... the result will be the same every time... It can be a Hoyt Vantage X8 or Pro Elite with X-10 Pro Tours.... or it can be a Miles Keller XI with a 5" over draw with sawed off 2213s.... the weakest point in the entire system is right where the hand meets the grip and what lies directly between the ears and just aft of the nose (read: the shooter).

When I was in college and poor as dirt... I shot wal-mart arrows to the exclusion of everything else. What I didn't have was any advice on which arrow to shoot.... and I ended up shooting Thunderstorm 30-50s off an UltraTec at 29" and 73#s.... I've got one upstairs still that I killed 6 deer, two hogs and several different species of trees with... still servicable... though I realize in hindsight the danger of the situation... but like I wrote before... you don't go to wal-mart for great advice on highly technical goods and products. Fortunately... we have sites like this one where someone can read up on what they should be looking for.