Caro doesn't need to hit more winners with her forehand. She just needs to win more points with her forehand.
The "winners" stat is so deceptive. I saw her match against Voegele, and she likely had more forehand winners than usual in that match despite the loss. However, this does not tell the story of how bad her forehand was during the match. There were numerous points in which she got herself inside the baseline and in a good position to finish the point only to hit a short FH with not nearly enough angle. The result of which was that Caroline was then out of position and Voegele had an easy DTL winner. Had Caroline won half of these points, she probably would have won in straight sets.
I believe Sanchez was on the right track in trying to promote her inside-out forehand. I thought the same thing back at the start of 2012 and was optimistic of her improvement after her tight QF loss to Clijsters. I wrote an article about her game following that match (If you're interested, the link is here
). Of course, her serve has also regressed since then.
I posted a knee-jerk poll a few weeks back concerning her forehand and took a lot of grief for it. But I really believe this is the key that is holding her back. She's kind of like a horse running on three legs, and it's really amazing how good she was despite her handicap.