Hi my friend Kirk,
What is your understanding of conventional reality and ultimate reality ( and more specifically) their interface, experientially?
Interesting question. Just going by my own understanding, I would say that conventional reality is what we say is the case, or not, through words, which are the verbalization of ideas or concepts. For example, "this is written on Tuesday April 26" is a conventional truth. But since that is all conventional agreement, ultimately none of that really applies to experiential reality, which never announces what day it is, nor does it label itself in any way. Even when it would be nice if it would sometimes, so we could know just what meditation state we just attained
The distinction between experience-as-it-is, and experience-as-it-is-labeled, is basically how I would put it.
However, just because all labeling and conceptualizing can be set aside, we cannot then reverse course and proclaim, falsely, that the things which we originally took for granted as "existing" actually "do not exist" - just because we have set conceptualizing aside. Hence, we can deconstruct whatever conceptualizing we like about the room we are in, the fact remains that its physical reality can still fall down on our head and kill us. Similarly, set aside whatever conceptualizing you please about oxygen, the fact remains that our lungs do not function in a atmosphere of pure helium.
"When one thing is practiced & pursued, ignorance is abandoned, clear knowing arises, the conceit 'I am' is abandoned, latent tendencies are uprooted, fetters are abandoned. Which one thing? Mindfulness immersed in the body." -AN 1.230