the magic 17 minutes you have left till you die comes from a simple averaging calculation. in one case control was lost after 9 minutes, in another it took 25, so some smart guy came up with (YES!) 17 minutes.
and one of the situations i think about a lot.
if you ditch it, they will blame you for sinking a still-flyable plane in the ocean.
because you can't proof to them that you would have lost control some minutes later.
and if you don't ditch it, the report will state you were "too mission-minded/target-fixated"...