I think that there are so many mods out there that make just a slight bit of difference if any. Maybe after all of them put together collectively may give "some" power.
The turbo discharge pipe, intake, throttle inlet pipe, intercooler tubes, throttle body tube, and lightweight pulley are some of the parts that singly may give nothing noticeable. But, may all together remove restrictions, reduce weight, and, I'll say it, look better.
Being realistic when considering mods, we know there are only certain things which give noticeable gains; bigger turbo, remap, internals, and file-supporting or required mods(intake, fueling, tbe, and fmic).
Please don't fault me for the items listed being completely accurate or not. I'm only making the point that there are "power mods" and there are "other mods".