I switched to BBF earlier in the year on my 7DII and tried this week on the 5D. As far as I am aware I have set it up correctly on both cameras and I use a mixture of AI servo and single shot depending on the subject. When I release the button on the back the subject looks in focus through the viewfinder and I then press the shutter. However when I review the images in LR or DPP, often none of the images show any AF points locked. Most of the images however look in focus. I have even had this with landscapes. Does BBF prevent software showing locked AF points, or more likely am I making silly mistake? If so, what?