It was commented that a quick test flight doesn't pick up long term damage. But you don't need to be able to spot long term damage immediately. The point is that a progressive test program can be carried out. You don't need all the information at once. If you can send up aeroplanes and they don't show apparent damage in several hours flying, then you know that things can at least start moving again, even if you do engine inspections after every flight to start with - that would at least be something.
And most aircraft on long-ish haul will only spend max one hour in the affected region/level per flight. That's not a long time, and you can boroscope after each rotation to make sure.
Its not rocket science, you just need to realise that the world is not a risk-free place - and aviation is not a risk-free industry. But the modern politician/civil servant is so frightened of his/her own shadow, they can no longer make rational decisions.
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