There's a 2/3 chance of 2 bits of entropy and a 1/3 chance of 1 bit of entropy, meaning an average of 1.666... bits of entropy per square. 9*1.666 = 15 bits.
Yep. I'll have to stop announcing releases during the night.
This means 128/15 ~= 8.5 scramblings on average. I'll change it on my post.
Having said that, I still wouldn't recommend this method for the reasons I discussed above. Scrambling the cube manually is not going to produce the same kind of entropy as rolling a dice or flipping a coin since you are consciously deciding every move to make as well as which face to read from.
It is surely not recommended, since the result isn't completely unpredictable,
as you said the user knows what he's doin'. I did it only for fun and I discourage anyone from using it for anything above a million satoshis. The dice is, by far, the greatest option. On a future release I'll warn the user about that.
P.S. i just noticed you haven't update download link for newest version on first page, you might want to change it.
Thanks. I had totally forgotten it.
Further, each square you enter decreases the entropy of all subsequent squares you enter until you scramble the cube again.
As long as you scramble the cube each time you submit a side, I don't get how that applies. Wouldn't that be true only if you mix it once and submitting the 6 sides as they were?