Dark Knight Skill Ambiguity / Text Bugs?

So I've been using (and loving the play style of) Dark Knight the past few days, having been a PLD for the past few months, it's a breath of fresh, lovely, dark and wrist slitting air.

I just have a few bugbears with it and wanted to know what other people thought, mainly around how abilities are worded.

So on your main enmity combo HS > SS > PS, the wording on Power Slash tool-tip states:

Delivers an attack with a potency of 100.
Additional Effect: Increased enmity
Combo Action: Spinning Slash
Combo Potency: 300

But then, once Dark Arts is obtained, the tool-tip adds:

Dark Arts Combo Effect: Increased enmity.

It looks like Dark Arts adds an effect the skill already has, unless I'm reading it wrong, does it do increased enmity twice? Or does it mean I can use Dark Arts and Power Slash without having to combo into it with HS > SS? Seems very confusing.

Additionals:

Another one is the Low Blow, the original tool-tip states:

Delivers an attack with a potency of 100.
Additional Effect: Stun Duration: 5s (PvP 3s)
Additional Effect: 30% chance that next parry will reset the recast timer

Then the trait Low Blows adds:

Grants a 30% chance that your next parry will reset the Low Blow recast timer.

It looks like the trait adds something that the original ability already had. It looks to me like a text bug, but I thought I'd put the question out there either way as some of the wording on the DRK abilities is a bit ambiguous.

Dark arts on power Slash adds even more Enmity than it normally has and doesn't require the combo. That means for quick aggro you could dark arts without it(but that is dumb) or add it on the combo for toms of aggro. Thus counters he fact that dark Knights don't spam the Enmity combo while tanking and let's them focus on soul eater spam. Otger thanks use their Enmity combos more often(pal for debuffs and war for damage)

That makes a lot of sense, cheers for the response!

The traits add it to the main tooltip. It helps so you dont have to remember or go into traits to see what it changed.