I can't believe you are still bickering about that healing issue.
Because it's a non-issue. In you above example all the other clanner had to do was team with someone 150.
Not even you. ANYONE 150.
A little preperation goes a long way.
I bring my wife, a level 100 doc with me on 150+ tower raids all the time. I just team with her, and she can heal anyone up to level 200. But at the same time, she can be attacked by anyone up to level 200.
In addition to having my wife in the team, I also make sure that I have someone 150 in my team on a 150 tower raid, so that I can recieve heals from a level 200 Omni doc.
If that person wants to be healed by someone outside of his PVP bracket, he need to open himself up for attack by people outside of his PVP bracket. It's 100% as simple as that.