The turnaround vision is getting harder and harder to see. GoPro's (GPRO -7.29%) turnaround isn't taking hold, and the company has once again seen its stock drop like a rock this week. According to data provided by S&P Global Market Intelligence, shares fell as much as 17.7% during the week and are down 16.7% at 3 p.m. ET on Friday. From bad to worse GoPro announced first-quarter earnings this week, and there wasn't a lot to like. Revenue fell 11% from a year ago to $155 million, generally accepted accounti ...