Hence the Roman Catholic church is not the largest religion on the planet
Your post factually falls as the article never says that Catholicism is the "largest religion on the planet." It references it as "the planet's largest religious body" which is accurate. You are treating Muslims as all being members of one body, which is not so. They are divided into many specific sects and camps.
” Readers interested in the the subject — whether as Catholics or Christians or simply because they want to understand why the adoption of Kasper’s proposal could lead to an internal crisis in the life of the planet’s largest religious body “
I treat muslims as an entity because they act that way when dealing with non-muslims. Once the rid the world of the ‘nonbelievers’ they turn on each other.