Words fail.

why.cs

        private static IEnumerable<string> AreYouSerious(UserPrincipal identity)
        {
            var enumerator = identity.GetAuthorizationGroups().GetEnumerator();

            while (enumerator.MoveNext())
            {
                Principal authorizationGroup = null;
                try
                {
                    authorizationGroup = enumerator.Current;
                }
                catch
                {
                }

                if (authorizationGroup != null)
                {
                    yield return authorizationGroup.Name;
                }
            }
        }