Is Siphon Strength bugged like Draw Strength?

[Siner]

Got siphon strength as was wondering if it bugged like draw strength. App1 does seem to stack with our other buff and gives like 10 str. Don't get me wrong it is still for all intent a worthless spell for the power cost and duration. But i like to upgrade my spell on the hope they will be fixed someday but I dont' want to do this if it actually makes it even more worthless by not stacking.

[Pheeb]

So Draw Strengh is really bugged?[expletive ninja'd by Faarbot] it - sounded like a useful one... ;(

[Siner]

yes i believe it was reported in the consolidated broken SK skills list that if you upgrade it, it doesn't stack with your conc-buff line. Was wondering if the same thing applies to siphon strength.