Which was bollocks, but we were to kind to mention it at the time............the same theory apparently explains trains as well, same that Idea is borked due to different standards across the world

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* And don't even go there with the loading gauge, one of the reasons why our current rings were so bloody small at the start of WW2 was due to the assistance that UK AFV's had to account for UK rails loading gauge where they were based, as opposed to continental loading gauge where the bloody things were going to be used - nobody thought to check the rail network between the barracks/manufacturers and the embarcation ports prior to WW2 to ensure the routing needed to move the AFV's to the ports would work with outsize loads, twats