Firstly, I agree with Roakeys comments about the frequency of hydro testing here in NZ. I've long argued that hydro testing must substabtially shorten a tanks life.
As far as tank testing goes I don't know that we can blame the scuba industry. Dive tanks are treated mo differently to any other pressure vessel and are subject to the same regulations. I've only dealt with 2 testing stations, one is a specialized cylinder tester and the other a dive store. Both are fussy almost to a fault. If they have the slightest doubt then the tank gets sent away for an x-ray. The incident in Tairua scared a lot people an prabably saw quite a few acts cleaned up. Today I wouldn't even waste my time trying to get a bottle filled that was even a day out of test. It just wouldn't happen.
As far as my comments about Luxfer goes, I have read of several incidents here in NZ and they ALL inovlved Luxfer tanks so as soon as I read the title of the original post I had to say to myself "I bet I know the make of that tank..."
OK, I know that's not very scientific. I admit I have absolutely no idea about what percentages of tanks in NZ are made by Luxfer, they're certainly very common.
Also, I beleive that our tanks are made in Australia so they could be slightly different to the US or UK versions.
Down here Luxfer is the Ford Pinto of dive tanks and you certainly won't find one strapped to my back.