“#1 However, It is still bit unclear that why Ghana saññā is such a critical concept?”
I don’t think it is critical in the sense that one must comprehend that to make progress. It is one factor that can be helpful. Different people make a “breakthrough” with different approaches. This may help some.
- That should answer question #2.
“#3 Why is it said that one understands the world properly only when all ten saṃyojana are removed i.e. with arhant phala?“
- One would lose ALL attachments to this world only at the Arahant stage when one’s “yathabhuta nana” becomes complete.
- One loses attachment in stages as one’s understanding becomes more and more precise.
