I'm fairly sure Double Strike used to be 20 force. Now it's at 25 force the same as clairvoyant strike. There's nothing in the patch notes concerning this change. Anyone able to confirm if I remember this correctly? I know it's only a change of 5 force but it made a big difference in terms of force conservation in pve for me.

As far as I recall, the two abilities had the same cost.

 

At least i'm sure about 1.4 because I respecced in infil during this patch (I never test this spec before - no appeal) and i noticed I could remove Double Strike of my action bar bacause while it has the same cost, Clairvoyant strike deals more, gives a buff and occurs the same procs. (I don't take the cost reducer from Balance)

Edited November 19, 2012 by Altheran

Double Strike and Clairvoyant Strike have both always had a base cost of 25 Force. You may be misremembering the cost reduction from Psychokinesis that reduces the Force cost of DS by 2 (down to 23) but has no effect upon CS. Since the only spec that doesn't take Psychokinesis is Infiltration, you may be confusing DS's functional cost of 23 Force as the "base" cost.

My shadow was started before 1.4 and DS cost 25 then.