Addressing Enfys Nest unique protection stacking

Reading her unique again:

So first attack is +40% protection (stacking). But then it very specific states "this Bonus Protection increases by an ADDITIONAL 40% each time".

Second attack adds 40% x 40% = 56%

Third adds 40% x 40% x 40% = 78% ?

Either that or it's:

40%
80%
120% after the third, so 240% added with 3 attacks.

If so it's completely ludicrous either way.

Even Ezra's bonus doesn't stack like that. If it did he'd be like a nuclear weapon after 3 or 4 turns.