Reading the thread I was thinking about this: the mk7 GTI has dual injection. As I read it, it seems that in very low revs-idle and high revs-limiter and PI in between. If someone with the Knowledge verify that with the actual revs which the dual port system works, this could clarify the differences we see with our MPG in combination with our driving styles. Someone may drive with too low revs, so only the one set of injectors are working, and this may be bad (or good) for the consumption. And some thoughts with some of us who like the conspiracy theories: maybe (surely) VW silently accepted that carbon deposits on the intake valves are something that they should rectify. So they added an algorithm to the ECU (given the liberty with the twin port injection) with which when some parameters meet (low speed of intake air in conjunction to low torque output or with the knock sensors or...anything, you name it, for example) it ups the amount of injected fuel through the PI. So the MPG goes downways. Like a DPF system in Diesel engines, which when it goes into regeneration mode, the car becomes...dieseloholic.
On a more realistic note, I think twin port injection has something to do with the MPG. Or it just failed because it is a new technology for VW and this ruined MPG in some of us. A member of APR in an other site which I read in 2008 said that VW was working on the calibration of the twin port injection system at the time. BUT it were laboratory checking and not out in the real world. Only then they could have a real statistic sample of the reliability of the system. Simple it seems, but it's not, I'm certain on it.
Oh well, History will tell...
