Kind of an odd question here... I have both a SP4 and a 2015 rMB on the way. I leave my SP4 charger in my road "IT Bag" and it has a USB-A slot on the charger. According to MS, the SP4 charger is 65W, higher than the 29W the rMB comes with. Question is if I use a USB A to USB C cable plugged into the port on the SP4 charger and into the rMB, will it charge, and will it charge without destroying the battery. Thanks in advance. --- Post Merged, Feb 3, 2017 --- Or alternatively I also carry an iPad Pro charger with me would a USB A to USB C cable charge the rMB off of the iPad Pro Wall Plug?