nobody with a manual will ever let you practice on their car
I’m sorry that happened to you. IMO folks are way more precious about their manual transmissions than they need to be. I’ve taught several people to drive stick – including myself, in a brand-new car I drove home from the dealer in rush-hour stop-and-go traffic – and it’s never hurt anything. (That brand-new car still had its original clutch when it was sadly totaled by a falling tree, 100k miles later.)
Same, I learned on a brand new car, on my own, and taught a couple other people with it, and it still had the original clutch when the transmission linkage broke at 187k (basically totaled at that point, just pulling out enough to get to the transmission would have cost more than the car was worth at that point… Low end Chevy’s don’t hold much value as it turns out)
The clutch is meant to slip, that’s literally how they work. As long as you aren’t riding it partially engaged for hundreds or thousands of miles, you probably won’t burn it out. If they were as delicate as people treated them, they wouldn’t have been the choice for racing for as long as they were after automatics hit the scene.
