Talon_Starfire, the Vanguard forums have been filled with so many questions from you recently, I've never seen anything like it.
First of all, are you talking about PvP or PvE tanking? Vanguard tanking in PvP is overshadowed, as it is, by Guardians and Shadows. However in this case you are gonna want to take both of these for maximum mitigation, I'm sure if you want the harpoon root you are talking about PvP since it is worthless in any other situation. I don't see the problem, you can easily get both and the harpoon root like this for example for PvP: http://www.torhead.com/skill-calc#801G0GrbRroGRZMcbZb.2
I'm talking about both PvP & PvE and not good at coming up with builds.