As to your question: No, the metering system adapts the automatic exposure to any fluctuations in transmission of any lens. This is the same when you put a dark filter in front of the lens: the automatic will compensate for this.
Only if you manually expose this lens and compare it to e.g. the 35/2.0D or 35/1.4G at trhe same exposure you can see that less light is transmitted to the sensor.
I was comparing my kit lens (Nikkor 18-105mm) against the Nikkor 35mm 1.8 lens because I was leaning towards the 35mm lens looked much softer than the kit lens. On a tripod though it looks pretty much the same. Must have been the Kit lens VR. What I found through was the same light issue.
After comparing them in Lightroom, I seen I have to boost the EV on the 35mm. So your comment about the cameras metering system adapting doesnt seem to make sense to me.
I had both lenses attached to a D90, on a tri pod, same lighting, set at the same F-Stop and focal length. If the camera were to adapt, wouldn't the post pics be the same exposure?
I was leaning towards the same question, "DO I need to set my camera for +.7EV when using this lens?"
It almost seems like I would need to in this case...right? Am I missing something?