Currently there is a bug where when you put power to shields, your shields will appear and energy will be drained, but it will not provide any damage reduction. Unsure as to the cause of this, however I have primarily noticed it right after desperate measures has activated on the Vindicta. However, this can also be seen on other ships, as I have also observed it on the Murometz and the Invictus, neither of which had desperate measures on them. I cannot say for certain whether or not setting power to engines or weapons is effected by this bug as well.
Edit: Possibly has something to do with getting hit by a status effect missile right as desperate measures is activated. Further testing required.