both results of [x rounds swiss pairing system] and [+1 round] are used in
(3) up and down by maximum 4 positions with ...
after the [x rounds swiss pairing system], the ranking results of Top 8, say A, B, ...H will follow the pairings below for [+1 round] : --
A vs H
B vs G
C vs F
D vs E
and assume H, B，F and D win in this [+1 round],
A vs H (w)
B(w) vs G
C vs F (w)
D(w) vs E
then the final ranking positions are : --
1 B win
2 D win
3 F win
4 H win
5 A
6 C
7 E
8 G
i.e. the winners B D F H and the losers A C E G use the ranking results from the [x rounds swiss pairing system].
You can look at it from the table below : --
5A move down 4 positions
1 B (win) move up 1 position
6C move down 3 positions
2 D (win) move up 2 positions
7E move down 2 positions
3 F (win)move up 3 positions
8G move down 1 position
4 H (win)move up 4 positions
It is logical for winners of [+1 round] to move up {maximum 4 positions} and losers of [+1 round] to move down {maximum 4 positions}.
Since this is critical [+1 round], could have 分先 if time permits, the concepts of winners in Top 4 and to be promoted still maintain and
do not need to play two more rounds ( as in x + 3 system )
since the [x rounds swiss pairing system] should carry weights in the final ranking for positions 1 to 4 and 5 to 8.
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