What is the occult? I have heard the name but never bothered to ask.
The occult is that which is of or perhaps associated with or concerned with supernatural phenomena inclusive of its influences, rites, and agencies. The occult is often considered to be numinous and as such dabbling in the occult has always been seen as risque because demonic or supernatural assistance is required to delve beyond the confines of natural human comprehension.
I would assume there is some level of research that goes into the game but that it is mostly confined to the lore of the Elder Scrolls saga, common knowledge on the occult due to popular fictions and films, and mythology. Would Bethesda include rituals and practices that are considered to be authentic in the game? No, I do not believe so. Such practices are contained within grimoires made usually of human skin or the like which are held in private collections for the most part - books that never see the light of day and are quite rare because many have been destroyed by religious groups. Access to them is restricted often for the sake of preservation or prestige.