                         | |||
| 21$-32D-51 | |||
| Position ID: 4HPKATDQc+QBMA Match ID: cIkGAAAAAAAA | |||
You have correctly isolated the concept, Tim.
Basically (for purposes of classifying a move's family): If playing the dice in either order leads to the IDENTICAL position, play the higher die first.
Obviously, this can make a difference (and then only in a small minority of cases, and also only for non-doublets) and only when a single checker is making the entire journey with both dice, and furthermore (by logic) if there is NO HIT along the way (e.g., say White has a blot on Blue's 10pt), when playing the dice in the two different orders (11/6/5 vs 11/10*/5) would NOT lead to identical positions.
As Mike has pointed out for the position diagrammed above, A (Attack) = 11/5 (broken down into the two half-moves of 11/6 6/5). This play is NOT also in the O (Outer) family; i.e., 11/10 10/5 is an invalid breakdown (though admittedly if someone did use O for a real-game play then I would tend to assume a mis-Nactation and that 11/5 was intended -- one needn't really fret about it). For other examples, see #55 and #56 (starting on page 64) of the Nactation tutorial, and Mike's two diagrams in this post.
Nack