You play 1. e4 and hit the clock. Your opponent looks at the board then back up at you- he’s got something up his sleeve: 1…Nc6. Do you dare play 2. d4 and enter the theory of the Nimzovich? No. You watched this ChessOpeningsExplained video and know that 2. Nf3 is the best continuation. An hour later your opponent stops the clock and tenders his resignation. Who knew watching a ten-minute video could do so much?