Randy wisely avoided the terms toe-in or toe-out. If you do use either term it really helps others if you clarify whether you consider the forward or aft edge of the rudder the "toe". Most people feel their interpretation is obviously correct, but even different boat manufacturers do not agree which is which . That said, FWIW, I believe the manual for my Phoenix specs 5* toe out with aft edges apart.
I think a lot of manufacturers spec aft edge apart as a safety default as this tends to create a low pressure area under the stern and keep the bow naturally up which keeps it safest when needed most in large following seas. The drawback is that most of the time that configuration requires a good deal of tabs down to compensate.
Aft edges closer encourages higher pressure under the middle stern with bow lower effect , less tab down needed normally & less bow lift when running down into that next big sea. Deep-v hulls with substantial deadrise angle carried aft tend to stern squat so they may be more likely to try aft edges closer, though many still employ the safety default setting mentioned above.
Besides the increase or decrease in lift effect, the other good reason for not having rudders set just parallel is to avoid rudder vibration . Aft ends set either in or out will keep some side pressure on both rudders and prevent flutter. if just flutter prevention is the priority, the minimum "toe" +/- that prevents flutter would be best.
Letting the second rudder loose to set itself may work, but I would imagine chances of flutter could be great. That trick seems likely to work better with the directional powered drives of O/B's & I/O's . But if you let one free then added another couple few degrees tiller angle in or out as desired to that one it should work OK.
As Skip suggests, a call to Ocean Yachts should get both the mfgr's rudder spec and their rationale for it. Just make sure they define 'toe".
Ocean: eMail: info@oceanyachtsinc.com Phone: 609-965-4616
Rudder Alignment....Toe In? 
