Help with Duelist/Gladiator Ascendancy Notable/Dual Wield Mastery

I don't know if it's intentional or something is just not working but from my (limited) understanding:

The Gladiator Ascendancy Notable Determined Survivor grants double bonuses for Dual Wielding,

And the Dual Wield Mastery grants "Dual Wielding does not inherently grant Chance to Block Attack Damage, +20% Chance to Block Spell Damage",

So as a Dual Wielding Gladiator, I should see my Chance to Block Spell Damage be at a base of 40% after ascending but it's still at 20%.

What am I missing here? Is this intentional? And if so, why? I don't see any good reason for it to be this way because this node effectively does literally (in the literal sense) nothing for my block chance for both attack and spell block if I take the node and mastery together.

Determined Survivor only affects the inherent bonuses from dual wielding (attack block and attack speed). It doesn't affect other sources like masteries (even if they're dual wielding masteries) or gear (like Rigwald weapons).

So it only doubles the inherent attack block and attack speed (resulting in 40% and 20% respectively), but you remove the inherent attack block so you lose half of the bonus from the ascendancy.

I see. Thanks for clarifying. I would hope GGG would consider changing the mastery to make it so that your inherent attack block is converted to inherent spell block so that this mastery could be affected by the ascendancy.