I always come up with more after I think about something for a while!
A proper trim will do no good if the cause of his laminitis is not addressed. The diet and lifestyle of the horse play a huge role in determining if he will be sound and ride-able or an “ouchy” pasture pet.
One of the most important aspects of a proper trim is trimming the hoof wall so it grows exactly parallel to the lamina. This ensures the lamina and the hoof wall are tightly connected preventing the coffin bone from sinking any more in the future. Another important aspect is keeping his heels low. This keeps the coffin bone parallel to the ground and prevents unnecessary stress on the lamina.
Here is an article that really goes into the details of laminitis (diet and trimming). It is really informative.