Here's an interesting story regarding Cartier, JLC et al and the genesis of the Reverso. It's probably well known to most people here but it's news to me and maybe some other WPS-ers.
It is from the Sotheby's catalog for an upcoming auction in Hong Kong April 24, 2026. https://www.sothebys.com/en/buy/auction/2026/important-watches-4/tank-reve