Does the Knight's Bladed Step require the shift to gain CA?

Question

Bladed Step, one of the Knight's Weapon Specialization options, has the following text:

Benefit: After you use power strike with a heavy blade, you can immediately shift 1 square to a square adjacent to an enemy. You then gain combat advantage against that enemy until the end of your next turn.

^{Heroes of the Fallen Lands, pg 136}

Obviously the shift itself is optional (from the use of the word "can"), but if you didn't want to change position, could you still gain combat advantage from this feature without moving? i.e. simply choose one enemy you're already adjacent to to gain combat advantage against, or shift 0 squares when you're already adjacent to an enemy?

Answer 1

If you are already adjacent to a foe then you do not need to shift to gain combat advantage against them.

You can always choose to move/shift/teleport fewer squares than the number given, including zero squares. If you are already adjacent to a foe, then you can shift zero squares (that is, stay put) and then gain combat advantage against that adjacent foe.

Note that Bladed Step explicitly grants combat advantage against a foe you end your shift adjacent to, however. If you choose not to shift and have no foes adjacent to you, you cannot gain combat advantage from Bladed Step.

Answer 2

The optional shift is not required in order to gain CA.

The benefit has two distinct sentences.

When you use Bladed Step:

1. you can immediately shift 1 square to a square adjacent to an enemy
2. you gain combat advantage against that enemy until the end of your next turn

There is no interdependency between #1 and #2 other than timing. #1 grants you optional movement which you are free not to take. Once #1 has resolved (you either did or did not shift), then #2 happens. All this does is prevent you from having CA while you shift (this could actually matter in rare cases).

I am not claiming that you can choose to shift 0 squares (separate issue). That is a red herring because you can choose to not shift at all.