CREATE POLICY bug ?

Hello,
i'm testing the new row security level functionality in postgresql 9.5.
To do that i run this script:

-----------cut here ----------------------

CREATE TABLE public.policy_tab
(
id bigint NOT NULL,
description character varying(160) NOT NULL,
usr name NOT NULL,
CONSTRAINT policy_tab_pk PRIMARY KEY (id)
);

ALTER TABLE public.policy_tab OWNER TO postgres;

GRANT ALL ON TABLE public.policy_tab TO public;

CREATE OR REPLACE VIEW public.policy_view AS
SELECT id,
description,
usr
FROM public.policy_tab;

ALTER TABLE public.policy_view
OWNER TO postgres;
GRANT ALL ON TABLE public.policy_view TO public;

ALTER TABLE public.policy_tab ENABLE ROW LEVEL SECURITY;

CREATE POLICY standard ON public.policy_tab
FOR ALL
TO PUBLIC
USING (usr = current_user);

INSERT INTO public.policy_tab (id, description, usr) VALUES (1,'uno','
manager(at)scuola247(dot)it');
INSERT INTO public.policy_tab (id, description, usr) VALUES (2,'due','
manager(at)scuola247(dot)it');
INSERT INTO public.policy_tab (id, description, usr) VALUES (3,'tre','
manager(at)scuola247(dot)it');
INSERT INTO public.policy_tab (id, description, usr) VALUES (4,'quattro','
teacher(at)scuola247(dot)it');
INSERT INTO public.policy_tab (id, description, usr) VALUES (5,'cinque','
teacher(at)scuola247(dot)it');

-----------cut here ----------------------

after that i run the query: "select * from public.policy_tab"

and the the oupt was what i excpected:

rows 1,2,3 for user: manager(at)scuola247(dot)it
rows 4,5 for user: teacher(at)scuola247(dot)it
rows 1,2,3,4,5 for user: postgres (the policy doesn't work for him)

but when i run the query: "select * from public.policy_view"

the ouput is the same (all rows) for all users

i'm doing some mistakes or this is a bug ?

thank you in advance for the time you would like dedicate to me.

Andrea Adami