The position on where it is will bump up the SW considerably though. If you put 14 grams at 3/9 your SW is going to be a lot less then if it's piled up at 10/12/2.
Of course you probably know that but it's good to put out there anyway.
The 14 grams is along the top of the frame, so it's going to have a considerable effect. Tsonga is one of strongest guys on the pro tour, so he probably notices the improved stability and plow but not so much the weight.