You don't lose "the complete use of your land" because a small part of it is considered historically significant, it's not the US. You do get to wait for them to figure out the boundary though.
As for your Wikipedia link, it's a good idea to actually read the whole text in it.
Again, it's not the US: are you just trying to come up with arguments that you can keep being angry about instead of knowing, or looking up, how this law's been used?
It's not, which is my point. Criticize it on the merits of how the law's used in Ireland instead of coming up with "things that happen" that don't happen.
As for your Wikipedia link, it's a good idea to actually read the whole text in it.