The first picture was just after the horse was deshod. A previous laminitis attack is evidenced by the heavy, broad rings in the heel area of the hoof wall. The hoof wall had been severely rasped when the horse was shod to remove the rings from the front portions of the hoof wall.
The second picture is 9 months later. You can see the hoof wall maintains the same angle more or less from coronary band to floor. If you look closedly you can see there are faint event lines. Some of them are from diet, others from wormers and vaccination. By carefully monitoring the appearance of these, it is possible to deduce what does and doesn't work for an individual horse.
This particular horse is an exceptional challenge and it is gratifying to have been able to get a reasonable angle all the way to the ground. Rock crunching comes and goes. A well intentioned but 'unfortunate' wormer is taking a long time to grow out.