[Mahler9th]

At least one of the posts I contributed to this thread mentioned an academic at Duke whom appears to have knowledge of the effects of implosions on humans. She is has also written about submersibles, including a CSA vessel incident that resulted in the loss of lives way back when.

Other posts provided links to information that suggests that at least one completed Titan (with hull monitoring) was tested at great ocean depths in an unmanned configuration at least on once, and at least one Titan hull was perhaps removed from service and examined after a dive.

Perhaps more will be learned.