It depends on what you would call complex. Describing a triply redundant system appears to me
to be of the same complexity as say parallel programming. Designing a high availability data
driven website (Google, Slashdot, et al) may even compare to a degree, it's a different
domain, but the problem is largely the same. Those inter-bank payment systems and flight
booking systems probably come close, where data lossage is an absolute no-no.
It might just be he calls it "very, very complex" because those standards are hard to read for
all the legalese they're couched in.
In other words, I'm guessing as much as you are.