Laws of the past' can mean anything. It doesn't have to mean any literal 'laws'. The king then used the word 'fate', which ties into the whole destiny thing far more than anything to do with tradition.
Laws of the Past at the very *least* strongly suggests following traditions if not actual laws. In either case, whether taken as a tradition or an actual law, the naming thing seems to be refered to. The destiny thing still doesn't explain why a girl named Tetra is suddenly called Zelda. It has no bearing on the topic at hand.
I'm not using any random theory. The whole Tetra/Zelda thing was a clear reference to the Sheik/Zelda thing, just played out differently in that Zelda didn't know. She changed appearance a lot. Of course her personality didn't change *much* (it did, she generally became more responsible), but her skin and hair changed dramatically, and of course her clothing did too. The whole Zelda thing is more than just some tradition. There's some serious magic going on.
The transformation in clothes, and slight changes in appearences is nothing like the concious transformation into Sheik. I agree that there is a similarity between OoT and WW with a key player turing out to be Zelda, but that is pretty much where the similarities end. The key thing to remember is that Zelda turned into Sheik, and then back into Zelda at a later date. In WW she has absolutely no recollection of the name Zelda, or of being a princess. She is Tetra, daughter of a pirate (might be wrong there, can't remember). She is then told she must abide by the laws of the past and is zapped into Zelda. It couldn't be a more obvious connection to the naming law in AoL.
I don't know about anyone else, but I would imagine Tetra was not told that she was a princess for her own protection. Also, she clearly didn't know that she was a princess until Daphnes revealed this to her. I mean look at her reaction:
Exactly. Its clear she had no idea about her bloodline or the whole princess business. However I don't think it was done for her own protection. I believe no one actually knew. The king himself wasn't even 100% earlier in the game. In his talk with Jabun he says he believes he may have finally found her, but it's clear he had to search her out instead of just look out for her. I also very much doubt that Tetras mum knew otherwise she would have told Tetra so she could pass on the tradition. It seems clear that knowledge of the bloodline was lost to Tetras family and it's the King who restored the bloodline by finding her.
Mohammed Ali