[Edi]

No idea about that. I haven't run any tests, and there is the random effect of the dice to consider, we don't know how much they add. You could do a test by setting e.g. a fire elemental fighting some fire immune unit and see what happens. You can reference the stats for the elemental from Zen's SCQR or the Dom2_DB_Units spreadsheet available from Arryn's site. Do it a few times and see how it goes.

Edi