I would also say that the amount of effort spent thinking before the game (or breaking your head during the game) also factors into it.
It's interesting how often this type of discussion happens in various things I take part in. My 3 main leisure activities are miniature gaming (mostly X-Wing and Armada), Discgolf (when there isn't snow on the ground) and MMO's.
In all 3 you can find discussions on casual vs competitive/hardcore. Which is interesting because none of them are played the same way. In a MMO there really is no winning or losing. In Discgolf you have tournaments and such, and someone can win the round. But you also have par to beat so even if I lose the round I can still have a good game because I shot -5. In Miniature gaming there's a winner and a loser and the most you can say was it was a close game.
In all 3 cases I think the casual vs competitive/hardcore is more about how much energy you put into it then how you actually play the game. For MMO's I play between 30 minutes to a hour or so a couple days a week. Yet I know what's in the latest patch and what skills work best, and so on. Am I a casual player or a hardcore one?
For Discgolf I actually play fairly well, last year my avg was 1.5 under par over 55 rounds. I play casual course and I play championship level courses. So I'm a decent golfer. Yet I never read discgolf forms, or articles or give much thought to it when I'm not playing.
For X-Wing and Armada... Well you can see my post count, and I run a league for both, play at store champions and regionals...
But back to the OP's point... I don't think it's correct. I tend to play a different list most times I play, sometimes a different list every game. Tournaments are the only time I play the same list more than twice in a row, but I will test them out for a few games ahead of time to make sure the list will work like I want.
