It's interesting that system mastery keeps coming up.
I think there is some benefit to system mastery, but I don't think Monte is explaining it very well.
I see it at its best in games like chess. "Out of the box", everyone has the same number of pieces, the pieces are fixed, and yet each piece has own ability. The big difference often comes in the experience of the players. Long-time players have developed strategies and know how to use the board pieces to great effect. They know that losing a pawn is a minor problem compared to the loss of a queen.
It's not a case of "pawns suck, queens rule" and you need to change the game rules so that all the pieces are pawns (or mid-range rooks/bishops) - or god forbid, every piece is a queen*. So long as a player is playing with
all the pieces, the game's fine as it is. And you should be able to play
Archon or
Nightmare chess without other people giving you the evil eye.
* Also, when comparing to D&D, it's better if each class represents a mix of all the pieces, not one specific piece; look at the entire side, instead of one single figure on that side (i.e., fighter ≠ pawn, wizard ≠ queen, but perhaps in certain edition's fighter = 16 pawns, wizard = 16 queens). The chess anology works best if each player is playing either white or black, not pawn, rook, knight, bishop or queen as their only piece. You start doing the latter, and the whole game falls apart.
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TL; DR - some system mastery is okay, so long as it's about
using what you have and not screwing with
what you have.