The AF Configuration Tool
Before I talk about the Canon AF configuration tool, I will briefly look at the 65 AF points.
The most obvious improvement on the 7d mkii over my 7d mki was the increased number of AF points, from 19 to 65. I am sure you agree this is a substantial increase.
As you can see in the image below, this gives the photographer almost edge to edge AF point coverage. All 65 of these AF points are available on lenses which have an aperture of f5.6.
What this means in reality is that the camera uses both the vertical and horizontal planes to find focus on the subject.

But what does this mean in reality?
If you are using a Sigma or Tamron 150-600mm lens, unfortunately you cannot reliably use cross type auto focus past 400mm. Beyond 400mm the lens effectively shuts down to f6.3 lens, and loses the ability to access the cross type points AF system.
If, however, like me you are using lenses such as the Canon EF 100-400 mkii f5.6 or the Canon EF 400mm f5.6, you can take full advantage of the entire grid of AF points in regard to cross point functionality.
The 65 Point Auto Focus System
Center Point AF
The center AF point, as with most professional and semi-professional bodies like the 7d mkii, has two additional features which make it very useful for us wildlife photographers.
First, if you are shooting at f8, the camera still maintains AF when using the single AF point. This is very useful for me when I add my 1.4 converter onto my 100-400mm mkii.
Secondly, if you are using a fast f2.8 lens, you can still benefit from the high precision diagonal cross type.
For the majority of wildlife photographers reading this article, the high precision point will not be an important feature, because we cannot afford or justify, for example, £12,500 for a 400mm prime f2.8 lens, (I wish!)
However, having a crop-sensor camera using a 100-400mm and a 1.4 converter, (this effectively lets me shoot auto-focus very effectively at f8, with a 560mm lens), this is a massive deal.
Lets talk about the Canon AF Configuration Tool
There is no argument, that the auto-focus system on the Canon 7D Mkii is a huge leap forward from the Canon 7D.
When I got my 7D Mkii it took me a while to surf all of the menus, but eventually I found the new Canon AF configuration tool.
This tool lets you move through six different ‘cases’ for certain auto-focus conditions.
Please note, that these cases only apply to AF when you have the camera set to AI Servo.
The AF configuration tool has six custom settings, or ‘Cases’, for capturing different types of motion. This system is also available on the Canon 1D x, 5D Mkiii, and there is some form of it on the 6D.
The rationale behind the configuration tool, is to assist you getting focus lock, quickly, when using AI Servo as the focusing mode, (as you are no doubt aware, AI Servo continuously focus on a moving subject.)
Each of the six cases contain pre-defined parameters, such as tracking sensitivity, acceleration and deceleration tracking, and AF point auto switching.
Practical Application
For a while now I have been experimenting with each case when out photographing birds in flight. I began by using Case #1 as it loaded by default. To be honest I was not that impressed with it.
I switched to Case #3 because I wanted faster, more sensitive AF tracking. It has worked very well for me and is my default case choice. At the moment.
Exploring the six cases
Case #1: Versatile multi purpose setting
As I expected, this case is a sort of generic case. In essence, it contains baseline settings which you can use as a starting point.

Case #2: Continue to track subjects, ignoring possible obstacles

Case 3: Instantly focus on subjects suddenly entering AF points
In this case, we want the AF to jump to the moving subject as soon as it enters our view finder.

For me, this case works very well. Primarily in wildlife photography, especially birds in flight, we are trying to track the subject throughout its entire movement. I find that this case works extremely well with BBF.
Case #4: For subjects that accelerate or decelerate quickly
Case #4 could be useful in scenarios where you are tracking a bird as they turn quickly and dive. This could be useful when tracking a predator running after its prey.

Case #5: For erratic subjects moving quickly in any direction

Case #6: For subjects that change speed and move erratically

Understanding the Canon AF Configuration Tool – a conclusion
To be perfectly honest it took me a long time to really understand the AF configuration tool. I have tried them all and prefer case #3 with BBF. I think if I was using the shutter button for acquiring focus I would probably switch to case #5. I have written an article about back button focus which you can read.
My suggestion is that you commit to spending some time using each of the individual cases and then properly assessing the results in Lightroom. If you are anything like me, making notes at the time of shooting would be beneficial as I seem to have regressed to Goldfish level of memory these days!
Anyway I hope you enjoyed reading the article as much as I enjoyed writing it. Please feel free to leave your comments below.
Roger