So; the rules breakdown is:
-UNSAVED WOUNDS are doubled for blasts/templates
-Wounds that are double toughness cause ID (duh)
And... wound allocation.
In 5th when someone hit 2 (let's say) scarab bases with an S6 blast/template you'd lose 4 bases (assuming you failed saves yadda yadda.)
In 6th, I can't tell by the wording if the base takes two ID wounds and dies, or if that second ID wound propagates to another model. It says the UNSAVED wound is doubled. Before you can remove the model it seems it just absorbs the second wound (if it has one to give) then goes *pop.*
Please help clarify how the rule works and why it works that way; the usage of the word Unsaved (and the manner in which you take saved in this edition) has utterly confused me.