I have a QJ 4x4x4 with Meffert-like tiles, and an Eastsheen 4x4x4 with Cubesmith tiles. I do NOT have a Meffert's 4x4x4, but I have seen and played with them a reasonable number of times for me to believe that their tiles are very similar to those on QJs.
Compare the first two pictures: On the QJ, one is able to see the white, red, yellow and orange tiles protruding from the U, R, D and L faces respectively. On the Eastsheen, one is only able to see 2 faces when the cube is held at the same angle.
In the third picture: While both cubes are tilted at the same angle in the x/[r] direction, the D tiles on the QJ are clearly visible while those on the Eastsheen are clearly not. Same goes for the fourth picture, only the cubes are tilted in the x'/[r'] direction (U: green, B: yellow).
I know my pictures are not that clear, if you have both a Meffert (or its clones) and an Eastsheen (or its clones), you can hold them at the same angle and see for yourself how ridiculously significant this unfair advantage is.
How it's unfair
Irrefutably, the cuber who uses the QJ has a very large look-ahead advantage during edge-pairing (I believe it is reasonable to assume that at least 90% of 4x4x4 solvers use reduction). There's also another less obvious advantage: Look-ahead during the 3x3x3 stage is relatively easier on the QJ, this advantage is IMO most pronounced during PLL recognition. Take a look at the first picture, now imagine if green were the U face, you'd be able to see all 4 sides just by looking from that angle, you don't even have to AUF or tilt the cube! Now that's not what I'd call "normal" PLL recognition, if this is legal, I'm gonna tile my 3x3x3 with tiles that are at least 2 mm thick before my next competition. (<--- Edit: Oops, I was a little rash there, forgot the WCA rules
Fine, 1.5 mm then!)
Most of us probably believe we got faster on the Meffert's purely because of its mechanism. But I have presented my reasons to believe that the improvement in our performances can also be largely attributed to the increase in ease of look-ahead.
This clearly goes against the WCA goal of more competitions in more countries with more people and more fun, under fair conditions.
Compare the first two pictures: On the QJ, one is able to see the white, red, yellow and orange tiles protruding from the U, R, D and L faces respectively. On the Eastsheen, one is only able to see 2 faces when the cube is held at the same angle.
In the third picture: While both cubes are tilted at the same angle in the x/[r] direction, the D tiles on the QJ are clearly visible while those on the Eastsheen are clearly not. Same goes for the fourth picture, only the cubes are tilted in the x'/[r'] direction (U: green, B: yellow).
I know my pictures are not that clear, if you have both a Meffert (or its clones) and an Eastsheen (or its clones), you can hold them at the same angle and see for yourself how ridiculously significant this unfair advantage is.
How it's unfair
Irrefutably, the cuber who uses the QJ has a very large look-ahead advantage during edge-pairing (I believe it is reasonable to assume that at least 90% of 4x4x4 solvers use reduction). There's also another less obvious advantage: Look-ahead during the 3x3x3 stage is relatively easier on the QJ, this advantage is IMO most pronounced during PLL recognition. Take a look at the first picture, now imagine if green were the U face, you'd be able to see all 4 sides just by looking from that angle, you don't even have to AUF or tilt the cube! Now that's not what I'd call "normal" PLL recognition, if this is legal, I'm gonna tile my 3x3x3 with tiles that are at least 2 mm thick before my next competition. (<--- Edit: Oops, I was a little rash there, forgot the WCA rules
Most of us probably believe we got faster on the Meffert's purely because of its mechanism. But I have presented my reasons to believe that the improvement in our performances can also be largely attributed to the increase in ease of look-ahead.
This clearly goes against the WCA goal of more competitions in more countries with more people and more fun, under fair conditions.
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