I think the issue arises because of the grey area between fairness and sportsmanship. Strictly speaking it’s not a fairness issue. Everyone can look up the game rules and posted league rules and unless otherwise agreed before the game begins then you’re working with regular dice and shouldn’t feel obligated to offer a re-roll under any circumstances unless you agree on the circumstances pre-game.
As far as sportsmanship goes, you’ve got to remember that everyone plays with different objectives in mind, such as:
- Having an evenly matched and engaging game
- Testing your best strategy against your opponent’s best
- Winning
Allowing a re-roll might make sense for the first two objectives, but not the last one.
There’s also a spectrum of gaming situations that complicate matters:
- League playoffs
- Live tournaments
- League high tier play
- League lower tier play
- Online non-league play
- Live friendly games
I think everyone is going to have a different point on the spectrum as to where sportsmanship trumps fairness. For me the line is below league play. Non-league games and live games are primarily for fun, so allowing a re-roll makes sense to me. In the league it’s perfectly acceptable to be playing for points and positioning (i.e. wins) so no one should feel obligated or entitled to a re-roll.
Of course if you’re playing a league game and you personally place a fun game ahead of winning, then by all means offer a re-roll, I’m just saying that in the league you shouldn’t expect it, and the other player shouldn’t feel bad about declining.
Managing the risk of extreme dice outcomes is a big part of what makes great players great.