-separated list of patterns to add to the exclude list. This is
-equivalent to the client specifying these patterns with the --exclude
-option except that the exclude list is not passed to the client and
-thus only apply on the server. Only one "exclude" option may be
-specified, but you can use "-" and "+" before patterns to specify
-exclude/include.
+separated list of patterns to add to the exclude list.
+This is only superficially equivalent
+to the client specifying these patterns with the --exclude option.
+Only one "exclude" option may be specified, but
+you can use "-" and "+" before patterns to specify exclude/include.
+
+Because this exclude list is not passed to the client it only applies on
+the server: that is, it excludes files received by a client when receiving
+from a server and files deleted on a server when sending to a server, but
+it doesn't exclude files sent from a client when sending to a server or
+files deleted on a client when receiving from a server.