Depending upon how you want to define it any player could be the difference in a close game, but that's a bit different from the idea that leaving any given player out could cost us the game. Of course by whatever definition it's also very possible the inclusion of any given player could cost us the game, it's a pretty silly metric to attempt TBH.
Because the implication there is that they basically demand selection, which you could say for those players I mentioned, but not for a player such as Cartwright.
Again I'd rather another forward on the bench, but I just don't reckon Cartwright is the player you have to have in our squad, I'd have an injured Nrown ahead of him, as long as he wasn't Black Knight type injured.