diff --git a/lib/ansible/cli/__init__.py b/lib/ansible/cli/__init__.py
index 48b62597a7..3e34d7ac7e 100644
--- a/lib/ansible/cli/__init__.py
+++ b/lib/ansible/cli/__init__.py
@@ -385,12 +385,16 @@ class CLI(with_metaclass(ABCMeta, object)):
     @staticmethod
     def unfrack_paths(option, opt, value, parser):
         paths = getattr(parser.values, option.dest)
+        if paths is None:
+            paths = []
+
         if isinstance(value, string_types):
-            paths[:0] = [unfrackpath(x) for x in value.split(os.pathsep)]
+            paths[:0] = [unfrackpath(x) for x in value.split(os.pathsep) if x]
         elif isinstance(value, list):
-            paths[:0] = [unfrackpath(x) for x in value]
+            paths[:0] = [unfrackpath(x) for x in value if x]
         else:
             pass  # FIXME: should we raise options error?
+
         setattr(parser.values, option.dest, paths)
 
     @staticmethod
@@ -419,8 +423,8 @@ class CLI(with_metaclass(ABCMeta, object)):
 
         if module_opts:
             parser.add_option('-M', '--module-path', dest='module_path', default=None,
-                              help="prepend path(s) to module library (default=%s)" % C.DEFAULT_MODULE_PATH,
-                              action="callback", callback=CLI.unfrack_path, type='str')
+                              help="prepend colon-separated path(s) to module library (default=%s)" % C.DEFAULT_MODULE_PATH,
+                              action="callback", callback=CLI.unfrack_paths, type='str')
         if runtask_opts:
             parser.add_option('-e', '--extra-vars', dest="extra_vars", action="append",
                               help="set additional variables as key=value or YAML/JSON, if filename prepend with @", default=[])
@@ -436,9 +440,6 @@ class CLI(with_metaclass(ABCMeta, object)):
                               help="vault password file", action="callback", callback=CLI.unfrack_paths, type='string')
             parser.add_option('--new-vault-password-file', default=[], dest='new_vault_password_files',
                               help="new vault password file for rekey", action="callback", callback=CLI.unfrack_paths, type='string')
-            parser.add_option('--output', default=None, dest='output_file',
-                              help='output file name for encrypt or decrypt; use - for stdout',
-                              action="callback", callback=CLI.unfrack_path, type='string'),
             parser.add_option('--vault-id', default=[], dest='vault_ids', action='append', type='string',
                               help='the vault identity to use')
             parser.add_option('--new-vault-id', default=None, dest='new_vault_id', type='string',
diff --git a/lib/ansible/cli/vault.py b/lib/ansible/cli/vault.py
index 7487235537..efd7d887e8 100644
--- a/lib/ansible/cli/vault.py
+++ b/lib/ansible/cli/vault.py
@@ -66,12 +66,20 @@ class VaultCLI(CLI):
         self.new_encrypt_secret = None
         self.new_encrypt_vault_id = None
 
+        self.can_output = ['encrypt', 'decrypt', 'encrypt_string']
+
         super(VaultCLI, self).__init__(args)
 
     def set_action(self):
 
         super(VaultCLI, self).set_action()
 
+        # add output if needed
+        if self.action in self.can_output:
+            self.parser.add_option('--output', default=None, dest='output_file',
+                                   help='output file name for encrypt or decrypt; use - for stdout',
+                                   action="callback", callback=CLI.unfrack_path, type='string')
+
         # options specific to self.actions
         if self.action == "create":
             self.parser.set_usage("usage: %prog create [options] file_name")
@@ -113,16 +121,12 @@ class VaultCLI(CLI):
 
         display.verbosity = self.options.verbosity
 
-        can_output = ['encrypt', 'decrypt', 'encrypt_string']
-
         if self.options.vault_ids:
             for vault_id in self.options.vault_ids:
                 if u';' in vault_id:
                     raise AnsibleOptionsError("'%s' is not a valid vault id. The character ';' is not allowed in vault ids" % vault_id)
 
-        if self.action not in can_output:
-            if self.options.output_file:
-                raise AnsibleOptionsError("The --output option can be used only with ansible-vault %s" % '/'.join(can_output))
+        if self.action not in self.can_output:
             if len(self.args) == 0:
                 raise AnsibleOptionsError("Vault requires at least one filename as a parameter")
         else:
@@ -138,8 +142,7 @@ class VaultCLI(CLI):
             if '-' in self.args or len(self.args) == 0 or self.options.encrypt_string_stdin_name:
                 self.encrypt_string_read_stdin = True
 
-            # TODO: prompting from stdin and reading from stdin seem
-            #       mutually exclusive, but verify that.
+            # TODO: prompting from stdin and reading from stdin seem mutually exclusive, but verify that.
             if self.options.encrypt_string_prompt and self.encrypt_string_read_stdin:
                 raise AnsibleOptionsError('The --prompt option is not supported if also reading input from stdin')
 
diff --git a/lib/ansible/executor/task_queue_manager.py b/lib/ansible/executor/task_queue_manager.py
index faea2aff7f..239ce0bfe6 100644
--- a/lib/ansible/executor/task_queue_manager.py
+++ b/lib/ansible/executor/task_queue_manager.py
@@ -84,9 +84,9 @@ class TaskQueueManager:
         self._start_at_done = False
 
         # make sure any module paths (if specified) are added to the module_loader
-        if isinstance(options.module_path, list):
+        if options.module_path:
             for path in options.module_path:
-                if path is not None:
+                if path:
                     module_loader.add_directory(path)
 
         # a special flag to help us exit cleanly
diff --git a/lib/ansible/plugins/loader.py b/lib/ansible/plugins/loader.py
index 61721d086f..3fae7b7538 100644
--- a/lib/ansible/plugins/loader.py
+++ b/lib/ansible/plugins/loader.py
@@ -229,6 +229,7 @@ class PluginLoader:
                 # append the directory and invalidate the path cache
                 self._extra_dirs.append(directory)
                 self._paths = None
+                display.debug('Added %s to loader search path' % (directory))
 
     def find_plugin(self, name, mod_type='', ignore_deprecated=False, check_aliases=False):
         ''' Find a plugin named name '''