Three times Murrayfield became a molten cauldron of noise, fathers and sons high-fiving each other amid the tumult. These scenes were all kindled by the same man: the blond bullet that is Scotland’s Duhan van der Merwe, whose electrifying pace once again ripped England to ribbons. The more you watched him, the more you saw a player dazzled by his own talent, visibly beaming whenever the ball bounced obligingly into his hands. And the more you wondered, as 67,000 fans stood to salute his hat-tric