A friend of mine going short haul for the first time summarised it like this. 'You are never really tired when you go to work, it's almost impossible to f^&*K up!'
Having worked in both LH and SH I agree entirely that the body numbing fatigue Jet Lag induces is something I never want to endure again.
Your friends statement regarding fatigue issues in SH is hubris in the extreme.
Picture multiple consecutive 04:45 sign on, 4 sector days in 4 seperate aircraft with 40 minute turnarounds, 12 hour two crew duty limits (extendable to 14) all whilst having min rest in salubrious accomodations like "The Vibe Hotel" in Kings Cross.