Mollify makeinfo with regard to this issue:
$ makeinfo --output=mit-scheme-user.info user.texinfo
user.texinfo:1552: warning: @strong{Note...} produces a spurious cross-reference in Info; reword to avoid that.
The relevant portion of the manual states:
Caution: Do not use `@strong' with the word `Note'; Info will
mistake the combination for a cross reference. (It's usually
redundant, anyway.) Use a phrase such as *Please notice* or
*Caution* instead, or ...
to system tasks after the need for a garbage collection is detected and
before the garbage collector is started. (An example of such a system
task is changing the run-light to show ``gc'' when scheme is running
-under Emacs.) @strong{Note well} that you should not specify
+under Emacs.) @strong{Caution:} you should not specify
@var{safety-margin} unless you know what you are doing. If you specify
a value that is too small, you can put Scheme in an unusable state.
@end deffn