Hey thanks for that thought. I've posted the following link in another thread on this forum regarding vented hoods. It has some comments on suggested lift effects, vent location, and results from a VERY small scale test.
Link:
Bimmerforums posting about vented hoods
(raamaudio comments in this tread back in 2013...hah)
The one guy who did some testing suggested that placing the extractors as far forward as makes sense probably has the most positive overall effects. However, there are possible negatives associated with reducing overall airflow throughout the engine bay.