Beyond the Apex is a joke as well, the overtaking section is one page with the only advise to out brake your opponent...
Most overtaking happens at the end of long straights. This is because you can utilise the huge change in speed to your advantage, so overtaking here has a high rate of success.
When pursuing your rival, it is often effective to rattle their nerves by going tail-to-nose, getting right up behind them, and then going side-by-side.
They actually encourage going tail-to-nose in a laggy environment
The two examples for overtaking in GT7
The classic dive, assuming the black car sheepishly drives slowly on the outside.
The
This method prioritises acceleration out of the corner and overtaking by crossing your driving lines. Block your rival by making it look like you are taking the inside line of the corner and then cross their line as you accelerate out of the corner.
I'm guessing this is what they're trying to get at, the switchback. Not gonna work if you're behind at turn in lol.
Although far more common is the red car going deep trying to overtake, the blue car switching back to immediately regain the position at corner exit. Or the red car hugging the inside blocking switchback attempts.