diff --git a/client/handlers_test.go b/client/handlers_test.go
index 27e13c7..3645d48 100644
--- a/client/handlers_test.go
+++ b/client/handlers_test.go
@@ -129,103 +129,71 @@ func TestCTCP(t *testing.T) {
 
 // Test the handler for JOIN messages
 func TestJOIN(t *testing.T) {
-	// TODO(fluffle): This tests a lot of extraneous functionality that should
-	// be tested in nickchan_test. However, without mocking to ensure that
-	// those functions are called correctly, we have to check they work by
+	// TODO(fluffle): Without mocking to ensure that the various methods
+	// h_JOIN uses are called, we must check they do the right thing by
 	// verifying their expected side-effects instead. Fixing this requires
 	// significant effort to move Conn to being a mockable interface type
 	// instead of a concrete struct. I'm not sure how feasible this is :-/
+	//
+	// Instead, in this test we (so far) just verify the correct code paths
+	// are followed and trust that the unit tests for the various methods
+	// ensure that they do the right thing.
 
 	m, c := setUp(t)
 	defer tearDown(m, c)
 
-	// Assert that the nick set in setUp() is still "test" (just in case)
-	if c.Me.Nick != "test" {
-		t.Errorf("Tests will fail because Nick != 'test'.")
-	}
-
-	// Assert that we don't already know about our test channels
-	if len(c.chans) != 0 {
-		t.Errorf("Some channels are already known:")
-		for _, ch := range c.chans {
-			t.Logf(ch.String())
-		}
-	}
-
 	// Use #test1 to test expected behaviour
 	// Call handler with JOIN by test to #test1
 	c.h_JOIN(parseLine(":test!test@somehost.com JOIN :#test1"))
 
-	// Verify that we now know about #test1
-	test1 := c.GetChannel("#test1")
-	if test1 == nil || len(c.chans) != 1 {
-		t.Errorf("Channel #test1 not tracked correctly:")
-		for _, ch := range c.chans {
-			t.Logf(ch.String())
-		}
-	}
-
-	 // Verify we still only know about our own Nick
-	if len(c.nicks) != 1 {
-		t.Errorf("Other Nicks than ourselves exist:")
-		for _, n := range c.nicks {
-			t.Logf(n.String())
-		}
-	}
-
-	// Verify that the channel has us and only in it
-	if _, ok := test1.Nicks[c.Me]; !ok || len(test1.Nicks) != 1 {
-		t.Errorf("Channel #test1 contains wrong nicks [1].")
-	}
-
-	// Verify that we're in the channel, and only that channel
-	if _, ok := c.Me.Channels[test1]; !ok || len(c.Me.Channels) != 1 {
-		t.Errorf("Nick (me) contains wrong channels.")
-	}
+	// Ensure we aren't triggering an error here
+	c.ExpectNoErrors()
 
 	// Verify that the MODE and WHO commands are sent correctly
 	m.Expect("MODE #test1")
 	m.Expect("WHO #test1")
 
+	// Simple verification that NewChannel was called for #test1
+	test1 := c.GetChannel("#test1")
+	if test1 == nil {
+		t.Errorf("No Channel for #test1 created on JOIN.")
+	}
+
 	// OK, now #test1 exists, JOIN another user we don't know about
 	c.h_JOIN(parseLine(":user1!ident1@host1.com JOIN :#test1"))
 
-	// Verify we created a new Nick for user1
-	user1 := c.GetNick("user1")
-	if user1 == nil || len(c.nicks) != 2 {
-		t.Errorf("Unexpected number of known Nicks (wanted 2):")
-		for _, n := range c.nicks {
-			t.Logf(n.String())
-		}
-	}
-
-	// Verify that test1 has us and user1 in, and that user1 is in test1.
-	if _, ok := test1.Nicks[user1]; !ok || len(test1.Nicks) != 2 {
-		t.Errorf("Channel #test1 contains wrong nicks [2].")
-	}
-
-	if _, ok := user1.Channels[test1]; !ok || len(user1.Channels) != 1 {
-		t.Errorf("Nick user1 contains wrong channels.")
-	}
+	// Again, expect no errors
+	c.ExpectNoErrors()
 
 	// Verify that the WHO command is sent correctly
 	m.Expect("WHO user1")
 
+	// Simple verification that NewNick was called for user1
+	user1 := c.GetNick("user1")
+	if user1 == nil {
+		t.Errorf("No Nick for user1 created on JOIN.")
+	}
+
 	// Now, JOIN a nick we *do* know about.
 	user2 := c.NewNick("user2", "ident2", "name two", "host2.com")
-
-	// Ensure that user2 is in no channels beforehand, etc.
-	if _, ok := test1.Nicks[user2]; ok || len(user2.Channels) != 0 {
-		t.Errorf("Nick user2 in unexpected channels.")
-	}
-
 	c.h_JOIN(parseLine(":user2!ident2@host2.com JOIN :#test1"))
-	if _, ok := test1.Nicks[user2]; !ok || len(test1.Nicks) != 3 {
-		t.Errorf("Channel #test1 contains wrong nicks [3].")
-	}
-	if _, ok := user2.Channels[test1]; !ok || len(user2.Channels) != 1 {
-		t.Errorf("Nick user2 contains wrong channels.")
-	}
+
 	// We already know about this user and channel, so nothing should be sent
+	c.ExpectNoErrors()
+	m.ExpectNothing()
+
+	// Simple verification that the state tracking has actually been done
+	if _, ok := test1.Nicks[user2]; !ok || len(test1.Nicks) != 3 {
+		t.Errorf("State tracking horked, hopefully other unit tests fail.")
+	}
+
+	// Test error paths -- unknown channel, unknown nick
+	c.h_JOIN(parseLine(":blah!moo@cows.com JOIN :#test2"))
+	c.ExpectError()
+	m.ExpectNothing()
+
+	// unknown channel, known nick that isn't Me.
+	c.h_JOIN(parseLine(":user2!ident2@host2.com JOIN :#test2"))
+	c.ExpectError()
 	m.ExpectNothing()
 }