The evidence for slip on {211} planes over mesoscopic distances recently obtained on disordered b.c.c. 50Fe–50Cr alloys by Kako, Isozaki, Takaki, and Abiko is interpreted in terms of a low specific energy for stacking faults on {211} planes and is related to the formation of coherent twins with {211} composition planes during plastic deformation at quite high temperatures. It is pointed out that one of the configurations of the a0〈111〉/2 screw dislocations considered by Sleeswyk is able to account for both the {211}‐slip and the nucleation of twinning.