I gather from the tone of your post that you're not too convinced that ozoneholiness is based on very good science, and that no matter what the data shows in the future, the ozone activists will find a way to cover their asses about it, disguising the fact that they really don't understand what is going on in the upper atmosphere or why there is an ozone hole. I also suspect you feel there is a political subtext to this, and that unfair expensive and restrictive measures are being forced on business that are not justified scientifically, primarily by leftist activists motivated by political rather than scientific reasons. I.e., the ozone hole may not have anything to do with industrial activities, and even if it does, it may not be a problem in the first place.

I know next to nothing about ozone hole dynamics, in fact, I gather no one really does, so lets summarize what we do know. Feel free to jump in if I've missed something below, or if I've misunderstood your arguments above.

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The ozone layer is important because it blocks solar UV which is harmful to life. I think this can be conceded. Explorers working on the icecap are already being forced to take UV protective measures. The polar seas are biologically highly productive for a variety of reasons and are probably vulnerable to extraordinary UV radiation. Plankton, in particular, seeks sunlight, so it gets exposed to UV during the long polar summers. How vulnerable to UV it actually is, I don't know.

CFCs carried into the upper atmosphere take part in a catalytic reaction that breaks down ozone, and that for some reason, this process occurs
most actively in the polar regions. By its very nature, this reaction
does not consume the CFCs themselves, so they continue with their mischief as more and more ozone gets trashed.

CFCs break down themselves to more harmless products eventually, although the time scales are not well understood. It also takes time for CFCs to migrate into the upper atmosphere. In other words, there is a time lag between changes at the surface in CFC and ozone concentrations at high altitudes. Those charts in your post, are they projections, measurements, estimates?

It is my understanding that neither of these two processes is understood in any detail, or we wouldn't be having this conversation. Both the chemistry and transport mechanisms for these gases must be very difficult to study, occuring at extreme altitudes and at very low concentrations. I don't think we have any platforms that operate at these altitudes, above balloons and below satellites.

To complicate the CFC budget, there is still CFC being produced today, and we have little idea how effectively it is being replaced by more innocuous substitutes. I know my old car still has the bad stuff in its AC, and I don't know if it will be properly disposed of when the vehicle is traded in. The same for the AC in my house, which I am replacing this year. And no one seems to be talking about what other countries are doing in this regard, particularly the Chinese. Even if there is no outlaw production or disposal of CFCs, there will still be releases from natural breakdown (old cars in junkyards, discarded refrigerators, and other industrial sources). It is also not clear how long it will take for this material to be absorbed into the ozone cycle and eventually, break down naturally in the atmosphere.

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From what I mention above, it's not surprising that it's going to be possible to interpret the ozone data for the next few years and just about any conclusion we want to draw from it will be possible. This is a very similar problem to the global warming issue, subject of a long and vitriolic post in these pages just a few days ago. It is very difficult to get data and just as hard to interpret it without a solid theoretical model for the process.

Having said that, we have to rely on the best data we have, and our best minds, and the usual panoply of science (peer-reviewed journals, etc). And we must be prepared to err on the side of caution. Fortunately, the current solution of switching to more benign refrigerants is not going to destroy the global economy, and at most, will be a temporary inconvenience and expense (the AC in my 2003 Sentra (the Death Star) isn't as effective as the one in my 1990 Sentra (the Milennium Falcon). I can afford it, and business will just pass on the cost to me. It also seems to me that the fears of ozone hole catastrophe may be exaggerated, but they are not unrealistic, there is some scientific consensus and the problem is potentially severe; in the absence of definitive evidence, the burden of proof should not be placed on the scientific community. It should be on those who wish to continue the use of CFCs.