I've not seen a major attempt to blind pre-prints, and given you have to remove some identifying information for blinding, I think that would be a tall order.
Why would that be a tall-order? Seems fairly simple and straight-forward, doesn't it?
You'd set up a server where people have accounts, but publishing pre-prints is anonymous by default, and identities can be revealed later.
In the current peer review system, people already have to produce papers with those identifiers removed. They can do exactly the same in the pre-print world, can't they?
