i dont think anything looks worse.
but i think that the its pretty simple basically, air takes the path of least resistance.
so the high pressure point or turbulent air at the bonnet/windscreen has got to be less that the air pressure that is trying to escape the bay.
It would be my opinion that it would work
because
the volume of air getting compressed up the back of the bay has got to be pretty great give the gaps/open element of bodywork at the front of an old car like ours.
raising the bay will actually reduce the turbulence at the bonnet/windscreen point becuase your tying them in better. increasing the angle.
adding some upward movement of air from the bay may improve this even better.
so im summary and in my opinion at a standstill hot air rises and an extra opening at the back of the bay will help (slightly) and when driving air pressure should push some extra air out also.
But it looks very.... escort rs turbo. (naff)
Phil