Not sure what's with the 'An Angry Baby Writes' act. The information about the Atlantic lock was something I read on an interesting website. Unfortunately, I can't remember where, and can no longer find it. However, it was not about the Atlantic lock on the Estonia it was about that type of lock in general. I think Atlantic lock might even be the name of the original manufacturers, in the same way we call things 'Stanley knife','Hoover' or 'Biro'. Thus the 'feel safe' factor was to do with vessels in pretty much open sea, or ocean. More to do with the ship owners and buyers than anything to do with Estonia passengers. Someone at the Papenburg shipyard in Germany would have made the decision to incorporate such a lock.
When you bear in mind the Finnish, Swedish and German car ferries already had the safety features The Herald of Free Enterprise did not (for example, the bow visor [gate to protect the car ramp], a hydraulically-activated sensor light when the Atlantic bolt was latched into place, flexible cctv cameras to surveille the car deck and fitted with an automatically activated (HRU) float-free EPIRB either side of the bridge [although the Estonia one mysteriously failed to activate despite apparently being released], together with the additional Atlantic lock, you can see it was nothing like the Herald of Free Enterprise in terms of lack of safety.