I worked at Land Rover for 27 years and took early retirement about 18 months ago, (the package was to good to turn down). Ford have been trying to offload Jaguar for some years now and could only do it by offering Land Rover as a sweetner. Land Rover have made a profit for the last 7 years and Jaguar are still haemoraging money. It started with them selling Aston Martin. The deal will probably secure the jobs for a few years, but eventually it will be moved to India where the labour is so much cheaper.
Production may be cheaper in India, but there's more to a car than cheap assembly.
Whilst they may shift production of volume models to the sub-continent, I seriously doubt that they would move the XK, XF & S-Type over there as these cars are the prestigious high-margin models where perceived image is more important than a 2% cut in labour costs.
Look at BMW & VW's ownership of Rolls & Bentley, they've not shifted production of these cars to the parent companies cheap labour plants in Eastern Europe, China & South America. Certain components may be sourced abroad, but the real craftsmanship is in the assembly, and that is where we lead the world. Yes an S Class Merc may be better built with laser thin panel gaps, but it's got no soul...
I've driven an LS400 and I felt like I was in a coma I was so insulated from the world outside.
I've never driven an S Class, but I've been in a couple and I still say it has no soul, it's too clinical, too perfect if you like. Now that may not be a bad thing, it depends on what you want from a car I suppose