I did, and the only optimization is partial, on deleted(). I've tried recreating the table and all the indexes without any changes.
I even went to the absurd thing of creating a more complext join to see the optimization level, like linking MASTER with MASTER_b and MASTER_b with DETAIL: The second join is fully optimized but the MASTER link to itself is only partially optimized, on deleted()

>I would still check Rushmore by SYS(3054), just to make sure that it's really full-optimizable.