The obvious argument against such a system is one of definitions and differences. You can't compare basketball to football (soccer). That statement is not entirely true, granted they are different games, very different one might say but they have commonalities. The goal for example is the same, to get an object ( in this case a ball ) into a protected area within the confines of the rules. The methods for the game differ, in basketball you use your hands and football you use your feet. Yet if i were go to someone and say, "What game am I talking about, in this game you need to get a ball into a net" There could be hundreds of answers to that, from hockey (field) to football (soccer) to lacrosse with interpretation even basketball! So how does this relate back to gaming?

Red sees duel as a mode, one which requires the same base skills. Described in a further post as key elements;
* Timing
* Control
* Aim
* Prediction
* Strategy

This is all very true; however the technicalities of such a skill vary with each game. Granted the underlying concepts are the same, however the ability to reach the levels of ability in varying degrees changes. If we accept that there are limits of ability and therefore there are degrees in all ability, who is to say the best mover in one game will be the best mover at another game. In theory there might be a game which due to the nature of it's movement would be impossible for a player to play. Yet they could be the best mover in another game.