> My subjective impression may be wrong. Maybe it is just that SRFI 210
> has turned into something that looks like an "amorphous" idea only
> because of the following discussions.

The situation is identical to SRFI 177, Portable keyword arguments. Both
came down to an aesthetic judgment.

177 worked as is, but no-one other than me liked the surface syntax, and
you thought it should support a more complete set of semantics (e.g.
custom default values for keyword args) whereas I was deliberately in
favor of limited semantics.

This one also works, but no-one other than me likes the syntax, and you
would like more complete semantics whereas I like the limited ones.

These are good outcomes - these discussions have taught me a lot about
aesthetics and made me question my assumptions. Scheme is a master class
in design. I still don't have a clear opinion on whether completeness is
a good or bad quality in the general case.