Siphoning strikes morph into Leeching strikes. The tool tip says it heals for 4 percent, but logs say it is only doing 2 percent heals. It feels very lack luster and not worth the trade off in its bugged form.
I hope it's 2% and the description is just wrong. 4% per hit to all resources is just wrong for healers and tanks, who can live with the damage reduction and become batteries using leeching strikes.