if you use true sacrifice function agaist any other capital ship like carrier/dread/rorqual target eventually is instantly destroyed BUT YOU will not have weapon timer for this. . basically if you are not warp scrambled and you fight over keepstar undock just use shadow fighters,kill target and dock up.
another problem is that not always shadows will succefully hit target. looks like shadows are unable to hit caldari capitals using true sacrifice ability,they will just keep permanent orbitting target and keep missing it.