Randomize

This takes two concepts and a call. While Random turns its concept on and off for alternate parts of the call, Randomize switches between the two concepts. The first given concept applies to the first part of the call, the second concept applies to the second part, and so on.

\syhlines{b4e,g4e,b1e,g1e} \syhlines{b4e,g4e,g3w,b3w}
4 2 4 2 1 3 1 3 4 2 4 2 3 1 3 1
before Randomize between Tandem and Stable, the Difference after