Unicode "no-op" Character?

[Richard Wordingham via Unicode]

On Wed, 3 Jul 2019 17:51:29 -0400
"Mark E. Shoulson via Unicode" <unicode at unicode.org> wrote:

> I think the idea being considered at the outset was not so complex as 
> these (and indeed, the point of the character was to avoid making
> these kinds of decisions).

Shawn Steele appeared to be claiming that there was no good, interesting
reason for separating base character and combining mark.  I was
refuting that notion.  Natural text boundaries can get very messy -
some languages have word boundaries that can be *within* an
indecomposable combining mark.

Richard.