My New Tank Spec vs. Choppa

During Gromils Crossing last night I got stuck far off by the keg capture point and was followed by a Choppa. I was instantly incited to test my new Tank build out on this lowly choppa. I, being mounted, began to head past him when he began flailing his choppas causing my Gyro-copter to malfunction. I quickly dismounted and charged into mortal combat with the ugly greenie. Within the first few seconds I had a great upper hand. My attacks were hitting him pretty hard and I got him to 50% with out hesitation. But once he got to 50% I had a rough time grinding his health down further. That damn tactic of his was healing him faster than I could DPS him! My grudges were full by this time and it was time to start spamming my new favorite ability, Oathstone. And it worked quite well. Keeping my positioning up I kept at him, but he was working me down really fast now. His knock downs left me taking 1k+ of damage since I couldn't defend w/ my shield (i only have 8k HP). The last few seconds were neck and neck. We were both at 5% health. My Earthshatter was on cool down and that is my primary source of crit damage. I was critting him with that earlier at about 1k. Quickly I popped my Oathstone and he ended up eating my shield as I hit him for 600HP.

It was far from an easy victory. I barely limped away from the fight with about 300HP. There are still many abilities that I failed to use that could have left me at a higher advantage.

What I need to incorporate into my RvR battles:

- Shield Of Reprisal. Knocking down my opponent for a few seconds would have really helped out. But I'm still not used to using a situational knockdown (one that can only be used when I block). Cave-in has really spoiled me.

-Taunt. I seem to have misplaced it and it wasn't in my action bar during the fight. That extra damage could have helped out, but I'm not really sure how much the taunt helps in RvR when someone like a Choppa is wailing on you. Edit: Taunt used to be a lot more useful. It seems that it only does an additional 3% damage now...

-Punishing Blow. yep, I completely forgot about this ability. If I had used it I could have caused two possible outcomes:
1) He would stop circling around me and fight me face to face making my blocks much more effective and making Oathsone a sure bet.
2) He would keep running circles and take some damage. This would have helped counter balance all the healing his tactic was doing.

-Away with ye. Didn't use it once. And if I had used it with the Punishing Blow, It would have been a great way to give myself a breather and force him to walk to me.

Yep, there is plenty of room for improvement when it comes to my RvR Tanking. I do think that I had my tactics set up pretty well though. Offering a good amount of damage output, but not limiting the use of my shield

Sweet Revenge + Raising Anger + Shield Mastery + Seasoned Veteran

Oh yeah, my current build.

Any other thoughts on how I could successfully run with my Tank in RvR would be very much appreciated.

Thanks!