So smarter dogs are better at tracking?
Yes and no. Not necessarily OR sure absolutely. What they're talking about is the genetic predisposition to take whichever kind of track. I'm not gonna be a good one to explain it but I can give you two examples.
1st. Hunting with CWard one day, I had one of my bitches cast out and come to a track she grinded on that track for 20-30 minutes and it turned up dry after a long run of it. My other bitch an hour later or so took an interest in a track and same deal, ground ground ground on it long time, long distance and eventually came out to the spot where the other bitch had first started earlier. when she hit the spot where she could smell her sister had already checked it, she quit and came back. Could not only smell the track, but she smelled that a dog she trusted had already come up empty on it and came back around to us in a hurry to go hunt some more.
2nd. This plays into the story from above, different dogs, same family though.
These curs took a track at the same time as another fellas plott hound, ground it out real hard, trailed in a good ways, heated it up and burned that sucker down. The curs took it pretty deep from what I gather and had the hog bayed, the hunters got there and as they were tying the hog the owner of the plott said "he's on a different hog. Turns out that he wasn't, he tracked and tracked and tracked and ended up bawling his way right smack into a hog that was already caught and tied.
This is NOT INTENDED TO BE DOWNING HOUNDS AT ALL!! alright?
What I'm saying is the hounds brain tells him not to worry wether another dog has covered it, or what else is happening (like a bay) they are bred and born to take tracks and finish them. This is what they mean about the brain determines the track they'll take
Once again not downing hounds or bragging on curs, these are just anecdotal examples.