I recently read an after-action report from a Europa Universalis III player involving the previously-thought-impossible feat of damn near pulling off a full world conquest as the Iroquois. At several points during the thread, people suggested that he continue the game onward into Victoria II, and the original writer's counter was "I only have time between work and married life to get good at one game."
Admittedly we're talking about Paradox here, a studio rather infamous for having games so complex that a large amount of effort is required in order to master their games (and even then, a certain degree of luck is often required to win as a non-major faction, and the further down the rabbit hole, the greater the difficulty), but I like to think I'm reasonably proficient (and have been even during times when I've been married/in a serious relationship and employed full-time) at a variety of games.
I'm downright legendary at Bethesda RPGs, having pulled off no-death runs utterly effortlessly in Fallout 3 and New Vegas (indeed, only the downright sadistic JE Sawyer Mod in NV provides any challenge anymore) and a lot _less_ effortlessly in Skyrim (but really, if I'm paying attention and not either screwing around or burdening myself with a bunch of extra difficulty rules like OSP, the game is a relative breeze).
Several games in the Total War series offer me almost no resistance; I'll often call a game of Rome: Total War by the time I've captured 15-20 provinces because the rest is a foregone conclusion between my army quality even as a weak/not intended for play faction and my economy. Napoleon Total War offers even less of a challenge, especially if I play as the Russians (my love of "In Soviet Russia Game Plays You" is a common enough theme here that you all know of it) where I have my back safely to the edge of the map, eliminating an entire war front.
And while we're on the subject, I've even gotten better than most at the first Crusader Kings, although I'm admittedly nowhere near as good at Crusader Kings II. I did pull off a very successful "Paradox 900" a few years back across their four 2D games (CK/EU2/Victoria 1/Hearts of Iron 2.) It was just me (as Sweden) and the Chinese, the world's two superpowers by the end.
And then there's NBA 2K12. Although on that game it is possible for the AI to beat me if it cheats badly enough (seems to happen about 1% of the time.)
Now yes, I am two things—-introverted and at times single minded about my hobby—-but I'm not so sure I buy into the idea that you need to overspecialize to truly get good at a game, and that a diversity of gaming skill is actually part of the fun.
Originally posted on Facebook, which is why the link artifacts are still in the text. I'm going to start writing about video games a bit more on this Kinja platform for benefit of those who have "followed" my comments.