I guess the discussion here might be fruitful (for myself & others), so allow me to drive on this topic, Bhante. 
I like keeping things as simple as possible. As a lay practitioner of some time, here’s what I’d say the main important takeaways regarding jhanas:
- Fulfilling the six preceding factors of the path, i.e. having right view and a life of sila, we cultivate conditions to have a pleasant abiding.
- In seclusion, withdrawing from sense world, we can cultivate a pleasant abiding, which enables us to have extraordinary mental experiences, getting gradually subtler and subtler, all the way to cessation of experience.
- By having the right view towards these experiences, we can observe the transient, impersonal, troublesome nature, & discover the delight of absence of experience.
- Understanding these three marks through these mental states, one can find release from craving & rebirth.
Would you find anything lacking in this blueprint?
Respectfully, with metta. 
