Fractional eight chains.

sdr> heads lead right
| 4B>  3G<  1B>  2G<
| 
| 4G>  3B<  1G>  2B<
sdr> eight chain 1/2
| 4B>  1B>
| 
| 3G<  2G<
| 
| 4G>  1G>
| 
| 3B<  2B<
sdr> eight chain 2
| 3B>  2G<  4B>  1G<
| 
| 3G>  2B<  4G>  1B<
sdr> eight chain 2 1/2
| 2B>  3B>
| 
| 1G<  4G<
| 
| 2G>  3G>
| 
| 1B<  4B<
sdr> eight chain 3 1/2
|           3G<
| 
|           1B>
| 4Gv  4Bv       2B^  2G^
|           3B<
| 
|           1G>
sdr> head boys run
|           1B<
| 
|           3G<
| 4Gv  4Bv       2B^  2G^
|           1G>
| 
|           3B>
sdr> promenade home
|      1Bv  3Gv
| 
| 4B>            2G<
| 
| 4G>            2B<
| 
|      1G^  3B^
sdr> /exit