I think the band can and does cure reflux for people who had it prior to banding, but I don't think those people are necessarily immune to reflux post-banding if they get over-tightened. I have no scientific basis for this belief, but I don't think there's any scientific basis for the other assumption either (correct me if I'm wrong).
I'm one of those who never had reflux prior to banding, and now I am very prone to it (even when I'm not really that tight). I have felt a lot of resentment about this, but in the long run I think it has helped to make the band work for me since I am afraid of overindulging and causing reflux.
-Yvonne
260/172/160, 5'8.5" tall
Midband July 2002