Tynawg, 200 bopd was the assumption put out on the first well drilled.......I am only using that figure without the benefit of a better figure - could be 0-600 bopd??
I will have to research the gravel part, but I suspect that it may be to do with reducing pressure to the bop and aid in the transport of the oil to the surface.
I suppose that so long as they don't follow the gravel up with cement and water all should be good......LOL