POTOMAC, Md.: Three years and 364 days since his last victory, Jason Day describes himself as “obsessed” with honing his new swing and improving his results, even if he never gets back to No. 1 in the world. There wasn’t much room for improvement Thursday as Day shot a 7-under 63 to take the first-round lead at the Wells Fargo Championship. Joel Dahmen was a shot back on what