diff --git a/examples/scratchnetuser.py b/examples/scratchnetuser.py
index 4b8b9fd..ccd20e9 100755
--- a/examples/scratchnetuser.py
+++ b/examples/scratchnetuser.py
@@ -38,12 +38,12 @@ def scratchNetUser( cname='controller', cargs='ptcp:' ):
     h1intf, sintf2 = linkIntfs( h1, switch )
 
     info( '*** Configuring control network\n' )
-    controller.setIP( '10.0.123.1/24', cintf )
-    switch.setIP( '10.0.123.2/24', sintf)
+    controller.setIP( '10.0.123.1/24', intf=cintf )
+    switch.setIP( '10.0.123.2/24', intf=sintf)
 
     info( '*** Configuring hosts\n' )
-    h0.setIP( '192.168.123.1/24', h0intf )
-    h1.setIP( '192.168.123.2/24', h1intf )
+    h0.setIP( '192.168.123.1/24', intf=h0intf )
+    h1.setIP( '192.168.123.2/24', intf=h1intf )
 
     info( '*** Network state:\n' )
     for node in controller, switch, h0, h1:
diff --git a/mininet/node.py b/mininet/node.py
index add10f3..63fd26c 100644
--- a/mininet/node.py
+++ b/mininet/node.py
@@ -358,14 +358,20 @@ class Node( object ):
                   'has no interfaces\n' )
 
     def intf( self, intf='' ):
-        """Return our interface object with given name,
-           or default intf if name is empty"""
+        """Return our interface object with given string name,
+           default intf if name is falsy (None, empty string, etc).
+           or the input intf arg.
+
+        Having this fcn return its arg for Intf objects makes it
+        easier to construct functions with flexible input args for
+        interfaces (those that accept both string names and Intf objects).
+        """
         if not intf:
             return self.defaultIntf()
         elif type( intf) is str:
             return self.nameToIntf[ intf ]
         else:
-            return None
+            return intf
 
     def connectionsTo( self, node):
         "Return [ intf1, intf2... ] for all intfs that connect self to node."
@@ -425,7 +431,7 @@ class Node( object ):
 
     def setIP( self, ip, prefixLen=8, intf=None ):
         """Set the IP address for an interface.
-           intf: interface name
+           intf: intf or intf name
            ip: IP address as a string
            prefixLen: prefix length, e.g. 8 for /8 or 16M addrs"""
         # This should probably be rethought