assertEquals(1, chain.loadCallCount);
        assertEquals(user, chain.lastLoadedUser);
    }

    // Test load with multiple chains (chained loading)
    public void test_load_multipleChains() {
        User user = createTestUser("user0");
        User user1 = createTestUser("user1");
        User user2 = createTestUser("user2");
        User user3 = createTestUser("user3");