No extra time involved - goods are at present carried by road through Britain and through the Channel Tunnel

To quote your little mate: Unfocused waffle.Do you ever check anything?

Example Dublin to Rotterdam via UK land bridge less than 20hours.
By single ferry journey 45 hours.

Nominally 8 hours ferry time using landbridge as opposed to 45 hours continuous ferry.

The clincher is that if it made any kind of economic sense they would have introduced super ferries years ago.