Vagueness in the Truism Classification

It is a bit confusing to have Truism 6N cover the act of making implicit assumptions into explicit parts of a narrative, while Truism 1 and 5N involve implicit assumptions. Implicit assumptions can either (a) be used in analysis of a sentence; or (b) become part of the explicit narrative.

Truism 1 states implicit assumptions about events.
Truism 5N says that facts are implicit assumptions.
Truism 6N says any implicit assumptions (not just 1 and 5N) can be made explicit.

I remain confused about this because I am not sure what are all the implications for an implicit assumption. It generates an optional narrative fragment that may appear explicitly (6N) or it can remain implicit and only appear in meta discussion.

Or, a truism may make sense of a later part of a sentence, or help anticipate it. Two different uses?

One more clarification (you can tell I am unsure): Truism 6N is N([Z],Z where the connector is a ',' and not a '::'. This is important because there is no automatic use of "but" to reverse polarities. So Trusim 1 is not expected to have a "but"-dependent polarity. And Truism 5N makes no assumptions about what known factual narratives it is referring to. I like the word "flout" which they use to indicate polarity reversal for "implicature" - an idea close to that of "truism" and very much the same as the affect of "but".