After finding and rereading the thread, it was on tanks that shouldn't be in service, I'm wondering if the theory Redbeard put forward may be correct. As the 2lber's round was solid it shouldn't be affected by humidity so rather than bouncing off the tanks the shells may have broken up on impact due to being a faulty batch.
It was the propellant that was the issue on the ships, that would affect the mv and penetration. However the Australians will, in any case, be bringing theit kit with them, and thats happily been shooting holes in Italian tanks for ages....