Doesn't surprise me. 4G is great control string. Roger had some big time issues with Forehand spraying with NO control. this might help some. and maybe this string will allow him to switch to bigger 98 or 100 sq inch frame.
Babolat Pure drive 2012, 55 lbs, Kirschbaum Proline X / X-1 biphase. Nalbandian backhand and Nadal forehand.