diff --git a/src/wormhole/test/test_wormhole.py b/src/wormhole/test/test_wormhole.py
index 824f23f..0dc8eef 100644
--- a/src/wormhole/test/test_wormhole.py
+++ b/src/wormhole/test/test_wormhole.py
@@ -127,7 +127,8 @@ class Wormholes(ServerBase, unittest.TestCase):
 
         version1 = yield w1.when_version()
         version2 = yield w2.when_version()
-        # TODO: add the ability to set app-versions
+        # app-versions are exercised properly in test_versions, this just
+        # tests the defaults
         self.assertEqual(version1, {})
         self.assertEqual(version2, {})
 
diff --git a/src/wormhole/wormhole.py b/src/wormhole/wormhole.py
index 0077020..a7a8606 100644
--- a/src/wormhole/wormhole.py
+++ b/src/wormhole/wormhole.py
@@ -131,7 +131,10 @@ class _DeferredWormhole(object):
     # from above
     def when_code(self):
         # TODO: consider throwing error unless one of allocate/set/input_code
-        # was called first
+        # was called first. It's legit to grab the Deferred before triggering
+        # the process that will cause it to fire, but forbidding that
+        # ordering would make it easier to cause programming errors that
+        # forget to trigger it entirely.
         if self._observer_result is not None:
             return defer.fail(self._observer_result)
         if self._code is not None: