The black bishop is needed solely to provide the set play, and some might consider that the problem would
be improved if it was omitted. Remember that set play means that there are two sequences, WBWBW and
BWBWBW.
The solution will appear here on Friday 13th February 2026.
Set 1...Bc8 2.Bb7 cxb7 3.Sc7 Sc6
1.Sb6 Sb5 2.Sc8 Sc7 3.Sa7 Sxa6
Fine parallel play by the knights. Chris Feather, in Black to play, opined that the set play was very ordinary and added nothing to the problem,
which was composed at a time when helpmates were dominated by the set play form.
Personally I think that the extra pair of parallel knight moves plus the matching bishop moves justify the addition of the black bishop.