@danderson 100%. I have some experience with AIIMS, which I think is the Australian version of MACS/ICS, and the sort of things that we talk about in SRE incident response are absolutely less sophisticated.
AIIMS includes an element of attribution to decision making, which is good in multi-agency response but I'm not sure is helpful in non-life-threatening incidents. But the delegation and span of control ideas are great and I've had good results teaching this in SRE orgs I've been a part of.