-
-Backtracking is disabled for the remainder of a sublist or group when
-certain conditions occur, described below. Backtracking is reenabled
-when a new alternative is established by @code{&optional}, @code{&rest},
-or @code{&or}. It is also reenabled initially when processing a
-sublist or group specification or an indirect specification.
-
-You might want to disable backtracking to commit to some alternative so
-that Edebug can provide a more specific syntax error message. Normally,
-if no alternative matches, Edebug reports that none matched, but if one
-alternative is committed to, Edebug can report how it failed to match.
-
-First, backtracking is disabled while matching any of the form
-specifications (i.e. @code{form}, @code{body}, @code{def-form}, and
+
+When a syntax error is detected, it might not be reported until much
+later after higher-level alternatives have been exhausted, and with the
+point positioned further from the real error. But if backtracking is
+disabled when an error occurs, it can be reported immediately. Note
+that backtracking is also reenabled automatically in several situations;
+it is reenabled when a new alternative is established by
+@code{&optional}, @code{&rest}, or @code{&or}, or at the start of
+processing a sublist, group, or indirect specification. The effect of
+enabling or disabling backtracking is limited to the remainder of the
+level currently being processed and lower levels.
+
+Backtracking is disabled while matching any of the
+form specifications (that is, @code{form}, @code{body}, @code{def-form}, and