Don't know if this will help or not, but I've used the OEM gui to create stored outlines. Unfortunately I have a vendor app that has started having performance problems and I've created 3 or 4 outlines in the past few weeks.

If you can use the gui, you are able to select the join order of the tables involved, then you can choose the join type (nested loops, hash, etc) and also the access method. It has been a little buggy with me (version 9.2) at times though. Sometimes it doesn't use the index I enter unless I change the join order first, then select the index I want, and then change the join order back. Strange, but other than that it has been working and has helped me solve my performance issues.

Just remembered this is part of the Tuning Pack in OEM so I realize many people don't want to pay for this. Never had to modify the tables directly, sorry...