I'd be willing to bet his core disagreement is light arrows and by saying 125 grain head he reduces this problem. Just a guess.
I hunted Idaho in 2002 with my wife, we had trouble getting her arrows up to 400 gr, had to switch to aluminum arrows to get it there and still spine right.
This makes sense , but if your bow is tuned to a particular setup , changing the tip weight can throw a bunch of other things off , and can be a reel pain , especially for new archers who are just starting to figure out how to tune their bow/arrows . And some people have a favorite head that they have had success with , building their confidence . This goes against 2 basic rules , KISS , and , if it ain't broke don't fix it . Of coarse those who like to fiddle are always breaking those rules anyway .