This guy (http://en.wikipedia.org/wiki/Emanuel_Lasker) was a chess generalist (able to play most position types comfortably), and chess world champion for 27 years. He succeeded by playing moves his opponents found most uncomfortable (murky tactics vs positional players, 'boring positional plays' vs flashy tactical players).

There is some disagreement today on whether Lasker was really about psychology or merely ahead of his time. My opinion is he did use psychology, but he also had very good positional sense which most of his contemporaries did not share (lots of Lasker's supposedly dubious plays are established modern lines). So he did play in questionable ways but not as questionable as might have seemed back in the day.

My favorite players are Capablanca, and Karpov (I don't like Lasker's style much, but the dude was amazing. His style most resembles machine play out of all players I know).