Most military ground vehicles were like that, designed to be multi-fuel compatable. They don't have to care about emissions, aren't trying to make max power, and aren't concerned about warranty work. They just want it to move when it needs to move and if supply lines are compromised, more options are more better.
There actually were some engineering nerds maybe 15-20 years ago who were experimenting with a commercial application for diesel/gas mix. It wasn't mixed in the tank, mind you. It had both a gas tank and a diesel tank separately. The vehicle itself then changed the ratio based on the load, temperature, etc. The result was a colder ignition temperature, so more energy going to moving the piston vs heat. I suppose it was either too expensive or too cumbersome to ever make it commercially, since it never became a thing.
Quick Google shows it was a thing, if a touch more recent than I remembered:
https://news.wisc.edu/hybrid-vehicle-team-to-test-drive-new-efficient-dual-fuel-engine/