diff --git a/git-tools/hooks/pre-commit b/git-tools/hooks/pre-commit
index bb667bf8ff..9e78edd90d 100755
--- a/git-tools/hooks/pre-commit
+++ b/git-tools/hooks/pre-commit
@@ -101,6 +101,30 @@ then
 	# if both are turned on php dumps the parse error twice.
 	# therefore here we try to grep for one version and
 	# if that yields no results grep for the other version.
+	#
+	# other fun php facts:
+	#
+	# 1. in cli, display_errors and log_errors have different
+	#    destinations by default. display_errors prints to
+	#    standard output and log_errors prints to standard error.
+	#    whether these destinations make sense is left
+	#    as an exercise for the reader.
+	# 2. as mentioned above, with all output turned on
+	#    php will print parse errors twice, one time on stdout
+	#    and one time on stderr.
+	# 2. it is possible to set both display_errors and log_errors
+	#    to off. if this is done php will print the text
+	#    "Errors parsing <file>" but will not say what
+	#    the errors are. useful behavior, this.
+	# 3. on my system display_errors defaults to on and
+	#    log_errors defaults to off, therefore providing
+	#    by default one copy of messages. your mileage may vary.
+	# 4. by setting display_errors=stderr and log_errors=on,
+	#    both sets of messages will be printed on stderr.
+	# 5. php-cgi binary, given display_errors=stderr and
+	#    log_errors=on, still prints both sets of messages
+	#    on stderr, but formats one set as an html fragment.
+	# 6. your entry here? ;)
 	$echo_e "$errors" | grep "^Parse error:"
 	if [ $? -ne 0 ]
 	then