I thought this might get some discussion going, which is very good.
I took the poor flight form comment as to mean the Ballistic co-efficient of the projectile, the ability of the bullet to fly through the air with the minumum of resistance.
BC of a Hydro would no doubt be terrible, but as others have said, at the ranges they are likely to be used, it wouldn't matter a bit.
(Has anyone used Hydro's for distances over 200 yards to hunt with, or check drop on paper?)
I still think if a mould was made with a self-centering pin for the depression in the nose, and a few small design tweaks to the radiused edge of the nose shape, they could be cast in a mould and be successfully made.
I suppose the question then would be "Why", when we already have a lot of good cast designs that do work.
I still think it would be a very interesting exercise though.

Regards,
David.