Return of Reckoning

The SH tactic Sneaky Stabbin states the ability Sneaky Strike will increase one's ability to defend against attacks by 15%. Is this an across the board additive? For example, does this mean if one has 10% parry, when Sneaky Strike is active (assuming Sneaky Stabbin is slotted), parry would become 25%. Similarly, if disrupt were 10%, it becomes 25%? Am I understanding this correctly?

Yes

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