I find it odd that you guys found that, as it improved gear change boost recovery noticably on mine.
The cold air side of it is no benefit. To me it's the fact that the air is moving from turbo to throttle body. When the dv opens in the usual position, the pressure wave has to travel the other way to relieve pressure and must cause some turbulence at the take off point (turbo outlet).
With it relocated, the air keeps traveling towards the throttle body, and relieves at the pressure block (throttle body)
On high boost applications, closing the throttle body when boost is building doesn't cause the usual hickup as the boost pressure is relieved.
Much smoother.
The fact that the valve runs colder also means that it needs serviceing less often.
Good mod imho