The problem isn't specific "hypothetical" scenarios. It's that (by current policy) we have to draw a line somewhere consistent. If we allow more things at the Delegate's discretion, we're only going to see weirder cases that need decisions, leading to complicated and possibly even more arbitrary looking rules.
Drawing lines is fine, allowing tiles of 1mm and not of 1.5mm is just plain inconsistent. Either ban all tiles or allow all (available) tiles. This would much more achieve your goal of making the Delegate's job easier.
Also, not everyone has the same definition of cheating. I would argue turning the top face of a stickerless cube 45 degrees to see the middle layer edges allows you to bypass the "basic concept" of a puzzle. Being lazy this way may not save you a measurable amount of time, but it is still cheating.
your use of cheating is wrong. No one within Board or WRC thinks that people would cheat with tiles (or stickerless cubes).
@
Sébastien: I like how Lucas (WRC) already does not agree with this in his next post. I would like it if you were a bit more careful with stating things like "your use of the word cheating
is wrong". I find it a bit unecessary to falsly try to simplify the reality this way in my disadvantage. Of course you are free to have a different opinion about the meaning of "cheating"

.
'Cheating' or not, tiles
are seen as an unwanted advantage people hypothetically can take care of (for which I still did not see any evidence), so this does not change my point.
The conclusion that those puzzles provide an advantage for looking ahead compared to the original concept uf the puzzles is trivial using logical thinking.
Yes I am well aware of the theoretical posibility. I never denied this, but only claim there is no evidence that tiles, transparent cubes or stickerless cubes can actually be used to get faster. For instance, when the stickerless cubes came out I did a lot of solves on it, because I like the fact that there is no black plastic interfering your recognition. Although I like the cube, I never managed to actually be faster on it than normal stickered cubes. (After this, the WCA announced they are illegal.)
If the only reason for the WCA/WRC is that it is slightly different than the "original concept of the puzzle" it does not make sense to allow 1mm tiles, but to ban mefferts and mf8 tiles. Only a total ban would make sense in that situation.
The 1mm change was not meant to throw many cubes in the trash can; that was a mistake. I was originally under the impression that mf8 tiles were under 1mm, else I would have tried to guard against lower than 1.2mm.
I am actually glad the limit was not set on 1.2mm, because allowing mf8 tiles and banning mefferts tiles would be a horrible decision I think. There is no reason mf8 tiles have different 'cheat'-possibilities (unfair advantage if you want) than mefferts tiles. Both are being used on a regular base in competition.
- It's unreasonable to ban all tiles, but 1mm bans tiles that are significantly thick. Yes, it's arbitrary, but it's a fairly reasonable line to draw for "thin" tiles.
I wouldn't use the word 'reasonable' to describe a ban on a high number of puzzles.
- It is impossible to prevent competitors from seeing others. This is an unfortunate fact of our competitions. However, some changes (e.g. requiring puzzle covers) have addressed this.
Yet I think this problem is
much more serious and deserves more time and effort than introducing dubious puzzle bans. I have seen tens if not hundreds occurences of people who should get a DNF or a competition ban because of this (probably it was not all on purpose). People can see whole crosses of solves by just looking at other people solving and here we are banning puzzles which provide a theoretical (though non-existent) advantage.
The only thing in 3h against having different tensions is "giving additional information", and this is only illegal with a very strict way of interpreting the regulations. If you want to start checking on this, you will make "the Delegate's job harder". There are at least 10 other ways to tell which face is which when blindfolded. (I will not name them, because I don't want to give any cuber tips on how to cheat)
- Consensus is that it would be more consistent to remove 7x7x7, but there were sufficiently many Delegates against this to put it off the table. Part of listening to the community/Delegates means that we can't exactly align with an ideal for everything. Everyone's major concern about 1.5mm shows that this is also very hard to do even when we try to be careful.
I agree with the consensus, but also that it was a good decision to not ban it for now. The issue does, however fit in line with the other questions, which is why I put it here.
As you (Lucas) stated several times you would like to see a good pro's and con's list I made you one. This is a list for the current regulations.
pro:
- a stricter line between what is allowed an what is not allowed and thus making the delegate's job easier.
con:
- delegates would in the worst case have to measure all tiles with a
metric ruler (Bob's post still cracks me up when I read it xD), or rather a caliper (
http://upload.wikimedia.org/wikipedia/commons/2/25/Vernier_caliper.png) which would make the Delegate's job more time-consuming (note: easier does not mean less work)
- allowing 1mm tiles still provides a possible way of having an 'unfair advantage' and does not in any way solve anything
- a significant amount of the cubes the community uses are now illegal