Top knotch dogs come from lesser parents?

my dad was a big coon hound guru he took it to a extreme all my growing up years. My uncle had some awesome money dogs. my dad would study genealogy of high power dogs and at the time knew alot of their genealogys from memory. I know i may be over simplifying it but he always said the best dogs out their were the result of two really good line bred dogs that were out crossed. He must have been right because we had some bad to the bone dogs by the time i was in my teens. A couple litters everyone was a top notch dog on coon. One male treed 70 in one season and was stolen a few days after the hides were sold. His mother was as my dad says " the finest dog I have ever seen in my life,She had everything" Line bred for several generations then outcrossed to another line bred.