For example, the Pantherish Twist (Acrobatics) talent says "You may use your Acrobatics skill in place of Parry when attempting a Defend Reaction". Even though you roll using your Acrobatics skill, the test is a still a Parry test. All you are doing is rolling towards a different target number and focus.
This means that Parry talents (e.g. Deflection) apply to the test, as does the parrying weapon quality, but Acrobatics talents (e.g. Agile) do not.
This has implications for attacks, as follows.
Some of them allow a skill substitution (e.g. Survival for the Flaming Brand display), some of them require the skill substitution (e.g. the Heed My Words (Command) talent), but they are still Persuade tests.
For example, the Captain (Command) talent does not apply to the Threaten attack granted by the Heed My Words (Command) talent, but the Naturally Charming (Persuade) talent does.
The Strong Arm Tactics (Persuade) talent is still broken, however. I'm thinking of replacing "You gain one additional d20 to any Persuade or Command test per rank of Strong-arm Tactics , up to the normal maximum of three bonus d20s. " with "any Momentum spent or points added to Doom to add bonus d20s to the Persuade test adds two dice instead of one, though the normal limit of three bonus d20s still applies."
In other words, make Strong Arm Tactics (a 200XP talent) the same as Deft Blade (also a 200XP talent).