I was speaking to the author (Tatsuo Ishii) around the reliability of PGPool-II when you did not have complete control over your SQL, he made it clear that if you cannot control what kinds of SQL is and isn't run from the application you and I quote "I will suggest you avoid pgpool-II.", He also noted that "Pgpool-II does not handle multi statements query very well" so pretty much count yourself out of using PGPool if you're using any multi-statement queries which is at least in our case a great deal of our SQL.