NOT to change it if it looks burnt??? Exactly opposite!

Look, at 78,000 miles, you probably should have changed the fluid before now. He doesn't want you blaming him if it dies at 80,000. But think this through yourself. There's gears, clutches, pumps, and seals in there. Proper, clean hydraulic fluid makes it all work and protects it from wear. Metal particles, crud, and varnish are not a plus! Possibly they are holding something together, but they won't for long. So get the old out before any more damage is done!

MrBSS