Back in the early 90's I had a Panda4x4, as an emergency stop gap between a dead 109lwb 6cyl and an early 90. It had a viscous, ird, rear diff arrangement, just like our Freelanders but with the bonus of a manually selectable 2 or 4 wd, on the main gearbox.
Cant help thinking that this should have been done on Freelander too, after all, we had to manually select 4wd on series as well as remembering to turn off our free wheel hubs.
That Panda was surprizingly capable too, on rough terrain, snow and mud, however it was slow, 80mph top, and screaming it's poor heart out at that speed, also quite thirsty considering it's 1L engine, my TD4 does better mpg, just!