Now THAT is fascinating. I resolved both puzzles as if the rule wasn't there, and sure enough I still had unique solutions.
What makes this a particularly curious discovery is that the fourth rule is one that I'm not absolutely certain is part of the original design! Although I think it is, I never actually got the instructions rigorously translated to prove it. At any rate, the presence of the rule makes the puzzles easier to solve, and far easier to construct, so I went with it.
I do know that future To Each Their Own puzzles I construct may require that rule to ensure a unique solution. It's fairly easy to picture a puzzle that has one or more letters that only appear once in the entire grid, and that without this rule could be trivially "solved" by having all the other letters occupy monominos. Neither of the two puzzles I've posted here have that luxury, but I need to look ahead to all instances of the design I may create when writing the rules. - ZM
no subject
What makes this a particularly curious discovery is that the fourth rule is one that I'm not absolutely certain is part of the original design! Although I think it is, I never actually got the instructions rigorously translated to prove it. At any rate, the presence of the rule makes the puzzles easier to solve, and far easier to construct, so I went with it.
I do know that future To Each Their Own puzzles I construct may require that rule to ensure a unique solution. It's fairly easy to picture a puzzle that has one or more letters that only appear once in the entire grid, and that without this rule could be trivially "solved" by having all the other letters occupy monominos. Neither of the two puzzles I've posted here have that luxury, but I need to look ahead to all instances of the design I may create when writing the rules. - ZM