FDW and transaction management

Greetings,

I am trying to understand the subject. I see in the documentation (
http://www.postgresql.org/docs/current/static/postgres-fdw.html) that

F.31.3. Transaction Management

During a query that references any remote tables on a foreign server,
postgres_fdw opens a transaction on the remote server if one is not already
open corresponding to the current local transaction. The remote transaction
is committed or aborted when the local transaction commits or aborts.
Savepoints are similarly managed by creating corresponding remote
savepoints.

The remote transaction uses SERIALIZABLE isolation level when the local
transaction has SERIALIZABLE isolation level; otherwise it uses REPEATABLE
READ isolation level. This choice ensures that if a query performs multiple
table scans on the remote server, it will get snapshot-consistent results
for all the scans. A consequence is that successive queries within a single
transaction will see the same data from the remote server, even if
concurrent updates are occurring on the remote server due to other
activities. That behavior would be expected anyway if the local transaction
uses SERIALIZABLE or REPEATABLE READ isolation level, but it might be
surprising for a READ COMMITTED local transaction. A future PostgreSQL release
might modify these rules.

Unfortunately, the Postgres Wiki (
https://wiki.postgresql.org/wiki/SQL/MED#No_transaction_management) states
quite the opposite:
No transaction management

FDW for PostgreSQL never emit transaction command such as BEGIN, ROLLBACK
and COMMIT. Thus, all SQL statements are executed in each transaction when
'autocommit' was set to 'on'.

What is the correct state of the subject?

--
Regards,
Michael Holzman