I'm sure this theory has been thrown around somewhere before, but here it is.
We all know Delta was frozen because of something that happened involving Eleanor.
We also know that Suchong was the one who was working on the protection bonds.
Delta, being the first bonded Big Daddy may not have been bonded at all... Perhaps Suchong was trying to REPLICATED the bond Delta shared with his little sister... or in this case
* Spoilers from here on out*
HIS DAUGHTER! If Eleanor was Delta's daughter, that would explain the protection bond. It wasn't chemical. It wasn't something Suchong needed to figure out, it was something he needed to REPRODUCE. So, in the audio diary where suchong talks about the protection bond, Eleanor is the little girl in the background. Delta is the one that drills the Sonova***** to the table. It makes sense because he didn't have the bond figured out completely yet CHEMICALLY, but the bond would've already existed with Delta.
Which leads me back to why Delta is in Hibernation.
Because he killed Suchong. Tennanbaum would have known all about it AND how to pull you out of it just as she helped Jack with Lot-22.
Am I way off base here?