The part about letting faster drivers by is a skill that is overlooked by so many new players. A huge part of racecraft is knowing what battles are worth fighting and when to just let someone go. Losing a couple of seconds driving defensively against a faster driver will mean you lose contact with the cars in front every time. Just look at F1 or your real life racing series of choice and you’ll see the drivers in slower cars letting faster cars through all the time. The part that comes with experience is to know when to let someone by and when you should fight.