The reason why people put uncommon saurians without the Efficiency trait between the ones with the trait is that they are hoping that someone will misclick and accidentaly buy the one without a trait. Strange things happen.
Used to be that you were guarnteed a saurian efficient BO at LC 6 or 7 (cant recall exact)
Used to do this all the time when they were worth so much more cash
Nope, this was never the case, which dates back to before the end of the Beta... Its just a matter of luck, with the window of opportunity between Lt. 6 and Lt.Cmdr. 6. Pushing more then 2 dozen different characters through this window, I was lucky enough to snag 2 Efficient Saurian Engineers. The rest of my 'Efficient' Saurians were all purchased off of the Exchange...