Last week I left you with this helpmate in 2 moves, composed by Chris Feather.
There are two solutions (remember that Black plays first):
1. Re5 Rh1 2. Rc4 Ra1#
1. Be5 Rxb7 2. Bc4 Ra5#
This demonstrates a double Grimshaw. In the first solution the black rooks interfere with the bishops, while in the second solution the bishops interfere with the rooks.
Hat tip to John Saunders who, in his latest CHESS column, reminds me of some 1960s opening theory. Can you find a good move for White here? (You’ll also see that former RJCC member Luke McShane is this month’s cover star.)