I drove from Indianapolis to Kansas City with no clutch in my JK. Of course it was mostly highway, but I did have to stop a few times. I was on the way to Moab and praying for a Jeep dealer open on Saturday and one that had a new slave cylinder in stock. Man, were prayers answered that day!If you lose the clutch you can shift by Rev-matching. To shift up you pull out of gear and apply gentle pressure to the next gear while letting the revs drop. When you have hit the right rpm the shifter will slide into gear. To downshift you have to goose the throttle to get the revs up to synchronous speed, then the shifter will slide in. It does take some practice but it can be done well with little to no grinding. Just don't stop
It isn't desirable, but in a pinch, it can be done.