FUNCTIONALITY OF PROMISCUOUS BINDING. “These regions allow for functionality such as engaging in the formation of dynamic heteromeric structures which can serve to increase local activity of an enzyme or store a collection of functionally related molecules for later use.”
http://www.biochemj.org/content/454/3/361?sa=X&ved=0CDkQ9QEwEWoVChMIzdjAo5n2xgIVovRyCh0HSAum