The following information reconfirms my favoritism for the multi-d6 method of gaming for Heroes and Other Worlds. You see a single die (d20) resolution will not produce an average result because of manufacturing vagaries. As a result, yes there are "lucky" or "unlucky" dice because of how they were made. Don't take my word for it, see the results below from Awesome dice blog.
Do Your Dice Roll True?
The founder of GameScience, Lou Zocchi, has long claimed that GameScience dice
roll more true than other gaming dice. In a well-known GenCon video
Zocchi explained why GameScience dice should roll more true.
His logic is that due to how dice are made
traditional RPG dice are actually put through a process similar to a
rock tumbler as part of the painting and polishing, and this process
causes the dice to have rounded edges. In theory the uneven rounding
gives the dice an inconsistent shape that favors certain sides.
GameScience dice are not put through this process, which is why they
retain their sharp edges and is also why their dice come uninked.
While Zocchi’s makes a good argument about egg-shaped d20s, what was lacking was any kind of actual testing
of how the dice roll. Nowhere were we able to find any tests of d20s —
either GameScience or traditional d20s — to determine whether or not
they roll true. As giant fans of dice and an impartial third party, we
decided to run a test ourselves and see just how randomly RPG d20s
We pitted GameScience precision dice against Chessex dice
(the largest RPG dice manufacturer) to see what science has to say.
For the principle test we used one Chessex d20 and one GameScience
d20, both brand new right out of the packaging. The GameScience d20 was
inked with a Sharpe to make it easier to read the results, but the dice
were not modified in any other way.
The dice were rolled by hand on a battlemat on a level table. For
this experiment the dice were rolled on the surface for at least two
feet and had to bounce off a flat backstop before coming to rest. This
is similar to the requirements of craps tables in casinos. Our logic is
that if this method successfully prevents cheating with six-sided dice,
it will more than suffice for d20 dice being rolled without any intent
to alter the results. (Since casinos are not losing money on gambling,
we assume they know what they’re doing).
Each die was rolled 10,000 times, and the results recorded.