ALTER TYPE recursion to typed tables

I'm working on propagating ALTER TYPE commands to typed tables. This is
currently prohibited. For example, take these regression test cases:

CREATE TYPE test_type2 AS (a int, b text);
CREATE TABLE test_tbl2 OF test_type2;
ALTER TYPE test_type2 ADD ATTRIBUTE c text; -- fails
ALTER TYPE test_type2 ALTER ATTRIBUTE b TYPE varchar; -- fails
ALTER TYPE test_type2 DROP ATTRIBUTE b; -- fails
ALTER TYPE test_type2 RENAME ATTRIBUTE b TO bb; -- fails

The actual implementation isn't very difficult, because the ALTER TABLE
code already knows everything about recursion.

Now I'm wondering what kind of syntax should be used to control this. I
think you don't want to automatically propagate such innocent looking
operations to tables in a potentially data-destroying manner. The
natural idea would be RESTRICT/CASCADE. This is currently only
associated with DROP operations, but I suppose ADD/ALTER/RENAME
ATTRIBUTE x ... CASCADE doesn't sound too odd.

Comments, other ideas?