First I should say I love diagrams; they're visual and easier to digest. In this case however, I'm enjoying it but also a question arises in my mind that really applies to the difficult difference between what constitutes the Vipassana Jhanas and the Samatha Jhanas. Take myself as an example. I've been told at least that I would probably fit into the Dark Night Nyanas, and so my highest point (let's discount for now my speculations that I often hit low Equanimity) is re-observation, which is on his model the 10th Nyana. It would seem to logically follow then that I could easily access up to the 3rd Samatha Jhana as well, no? And yet this doesn't really seem to be the case (though depending on your definition of absorption I may have already experienced a light, gradual version of it many a time already.) This has been hit upon many a time already, but I simply don't understand it.

Being good at getting to a particular stratum with one technique (investigation, in your case) doesn't make you good at accessing that stratum via the other technique (serenity meditation). This is because the vipassana jhanas and the shamatha jhanas are different things, even though they have similarities.

You CAN expect to more easily recognize the third shamatha jhana when you encounter it, because it will feel a lot like Dissolution. But practicing vipassana does not teach you how to practice shamatha, even if you sometimes encounter concentration phenomena in your vipassana practice.

Think of the strata of mind like a single coordinate in a system that has many other coordinates. Sort of like latitude, longitude, and altitude for describing points on Earth. The climates on the 70th latitude are all cold, but there are many different places on the 70th latitude. And you have to use different means to access different places. On water, you need a boat, but on land you need a land vehicle or airplane.

Unfortunately, being a good driver or pilot doesn't make you a good ship captain.