I can think of counter-examples, but none especially compelling, and am
convinced by Al's example that bound=? makes more sense.  I've pushed
the change to master.

A counter-example would be my current implementation of SRFI 147/148, which relied on the free-identifier=? comparison. But it is also not that compelling because it is possible to rewrite it, which I am currently doing.

As for the change to Chibi, you also have to apply the change here:

https://github.com/ashinn/chibi-scheme/blob/master/lib/init-7.scm#L832

(I forgot to mention that line in my earlier post as well.)

Marc
 

-- 
Alex