I am comfortable doing pull-ups, but do not keep a stable core, thereby emphasizing shoulder strength versus lat strength.
Similarly with hand stand holds, I have an arched back. His suspicion was core strength, but I would argue it is more a function of shoulder mobility.
Either way he recommended some books and I may consider starting over with progressions. Regardless of those steps, losing abdominal fat and improving overall mobility will lead to great strides in overall well being.