Your bog standard track walk to me is a waste of time, its something a team or coach does probably because its what they are expected to do. If I walk the track before the day starts I use it as a chance to chat with the driver, and they do most of the talking while I find out a bit more about what makes them tick. Instructions you deliver to a driver at 9am are generally forgotten anyway!
Studying the track for real benefits
There is however a very productive way to study the track, that actually helps drivers understand how to master corners.
Here's how I do it.
Warning - this method takes up to 10 minutes per corner. Also you might get some funny looks because you'll be crouching down and walking backwards a lot!
Start at the end.
Start with the result you want to achieve as you exit the corner. Examples: you need maximum speed onto a straight, or positioning ready for the following corner.
Get very familiar with your exit point
With the desired result from the corner in mind identify your exit point. Stand at that exit point and look for an identifying mark. It might be an exact point on the exit kerb, or maybe a mark on the asphalt.
Get very familiar with that mark, and walk BACKWARDS along the track toward the apex of the corner.
Crouch down so that your view of the track is as it would be when driving, and spot your chosen exit point. Burn this image into your mind because this will be what you'll be locking on to while you suffer 2 G loads, with scenery flashing past and other lunatics attempting to fire you off.
Get even more familiar with your apex
Now that you understand the desired exit you will know what kind of apex you need. It could be a late apex or a regular apex. Whichever it is, you need to locate it precisely and pick something you can easily spot. Again get very familiar with it and walk away from that apex backwards along the track.
Get to where you might turn in and crouch down. Study your chosen apex point so that you know exactly where it is. You now know how it will look from the kart, and you need to be very comfortable that you can pick it out with great confidence.
Now walk backwards away from the corner and keep looking to your apex point. Get as far away as you can before you reach another corner. You could be walking backwards along a straight until the corner apex is a long way off. Crouch down again and spot that apex, you need to be able to locate that apex from a distance confidently. If it is obscured you need to know now, and you need to be able to locate that point either directly or by using extra markers.
Now you know the critical points of that corner in real world terms better than anyone else who doesn't bother going through this procedure. This will give your subconscious critical information and free up processing power to make you drive faster!
Little extras that make a big difference
But don't stop there, walk forwards toward your corner keeping an eye on your apex. Now we are looking for peripheral markers. These would be braking indicators, and cornering marks that keep you clued up that you are positioned correctly as you drive the corner perfectly.
Pick a braking indicator. I say indicator because braking points change according to grip, and you'll only use it with peripheral vision. Typically there will be marks left by locked tyres, or marshal post in braking areas.
Look for an indicators for turn in point, when to get off the brake, get on the throttle and where you expect to reach full throttle. These indicators are luxury items that you will notice with peripheral vision. When you hit them with the correct inputs you'll get a feeling of confidence that things are going to plan. This is the detailed feedback that can put you in the zone.
I recommend you walk the whole corner over again, crouching down occasionally and take notes as you go. Map out the corner with all your details, and use this diagram as your first plan for taking the corner.
This is the serious driver's approach to mastering a corner. It takes time and effort and will set you apart from every other driver on the grid.