confirmation of scramble 'correctness'

[Timmah]

Sorry if this has been asked before, I did a search but don't really know how to word what I mean!!

So I use The Cube App for timing on my phone.

When I've done the scramble as per the app, how many faces do I need to look at, to confirm ALL faces are showing as expected?

I've been checking three, but wasn't sure if that was either overkill or not enough?

 

[cubenerd74]

For 3x3, Most of the time 2 or 3 is fine. If you really want to be sure, you should check all the sides.

 

[Thom S.]

Theoretically speaking, there are scrambles that look the same on 5 sides. For Example, start with a solved cube and flip the 4 Top Layer Edges. Take another cube, do a U Perm and then flip the 4 Top Layer Edges. If you deliberately don't look at the top side, those 2 scrambles look the same.

In practice, if you compare 3 directly touching sides (U, F, R for Example), you are good. The chance of you misscrambling in a way that produces a state which would look the same from 3 sides is astronomically low.

 

[Jorian Meeuse]

In practice, if you compare 3 directly touching sides (U, F, R for Example), you are good. The chance of you misscrambling in a way that produces a state which would look the same from 3 sides is astronomically low.

Same goes for only checking U and F.
Personally, I just trace the corner memo, because there is no way I scramble the corners correctly but not the edges, it takes only like 2-3 seconds per cube, I'll only have to compare the first cube I scramble with the sheet, and I'll catch any accidental corner twist if those were to happen.
It doesn't work for big cubes though.

 

[Timmah]

Theoretically speaking, there are scrambles that look the same on 5 sides. For Example, start with a solved cube and flip the 4 Top Layer Edges. Take another cube, do a U Perm and then flip the 4 Top Layer Edges. If you deliberately don't look at the top side, those 2 scrambles look the same.

In practice, if you compare 3 directly touching sides (U, F, R for Example), you are good. The chance of you misscrambling in a way that produces a state which would look the same from 3 sides is astronomically low.

Astronomically low being only a few in around 43 quintillion?