As for call/kw, 10 Scheme implementations currently support keywords in
their native call syntax. If we arrive at a good spec that is compatible
with them, perhaps more implementations will follow. Even if R7RS-large
uses a crutch like `call/kw` or `call`, most code might eventually be
able to avoid it and use ordinary procedure call syntax. `call/kw` or
`call` would be reserved for portable libraries, and applications could
use ordinary syntax. This would require standardizing the read syntax
for keywords at the call site (foo: vs :foo vs #:foo).

[Apologies for not cc'ing wg2; when I did, my message bounced. I should
finally join the group.]