Glad you brought that up..

If you have read any of my posts (or not), you may know that I have Glaucoma, and am doing the EB right now.

I don't have a slant board, or an inversion this or that, but have also read that this is important and did also wonder about the conflicting (or confusing!) information.
I know the same has been said about if you tend to have higher blood pressure - that bending over, or being upside down is not good for BP.

I have some thoughts on this, but do not want to answer because I am just making guesses, so unless we can find an answer in the FAQ (?) or if Uny has a minute to take a stab at it, I really don't know.

But, like you, 'inquiring minds wanna know'! and I too have an interest in the answer!