SC focus on wepon is not reducing power cost (Deathsight)

[Goro]

In my template I have 50 deathsight focus lvls on my melee wepon.

1. When casting scream of the dead with (deathsight mastery shade lifetap) my 50 focus level spell crafted item equipped, the nuke is consuming 4-5% power.
2. When casting scream of the dead with my 50 focus level CL staff equipped, the nuke is consuming 2-3%

Please inform me if this is working as intended.

Thanks

Goro

[Karen]

"Please inform me if this is working as intended."
This is not a bug report.