Yes that's true! It's best to not burn any fuel at all.
But I've burned a lot of fuel in a meantime, because we went to Bulgaria on holidays. And we've made more than 4500km during that trip. But we were driving Mietek (my wife's car). Anyway it wasn't hypermilling at all though it burned less than 5l/100km (47mpg US), even when it was fully loaded (5 passengers), lots of stuff in the trunk, 120-130km/h cruising speed for most of the time and A/C constantly on. Not bad, not bad at all, I would say
Unfortunately I've lost all fill ups data because of mobile phone failure, but I know the global amount of fuel burned and the distance. That's why I can tell that I was amazed how good FE it has.