Nope IGN said in thier review the console has to be turned on to charge th Pro Controller.
are you sure, i cant find it in the ign review, it only talks about the charging proces of the wiiu gamepad and not the wiiu pro controller(that looks like a 360 controller)
also how much time did you get out of the wiiu gamepad with a full charge, real world estemates (not the 3 to 5 hour bs from nintendo, same was said about 3ds and it didnt even last 3 hours)