If the missiles get parried by shield, they just miss. Protection and missile strenght don't come into the picture at any point when determining if the missile attack hits.
So the best possible protection from missiles in Dominion world is to wield a huge 5 m^2 sheet of paper (parry 15? protection 0). No missile would ever effect you then!
__________________
I have now officially moved to the
Dom3mods forums and do not actively use this account any more. You can stll contact me by PM's, since my account gives e-mail notifications on such occasions.
If you need to ask something about modding, you can contact me
here.
See this thread for the latest info concerning my mods.