The reason why the Lancaster and the Shackleton broke down into easily roadable chunks is more to do with the fact that they were built on the other side of Manchester and it made it easier to transport them to AVRO's airfield at Woodford where they were assembled and test flown. Incidentally the Shackleton that used to be on display in the science museum in central Manchester recently made a very similar trip into storage on what used to be the airfield at Woodford.