[userbinator]

> Why, for instance, did it suddenly decide that these particular chunks should be aligned to four bytes, and that this alignement should not be included in the size? Other chunks in other places are either unaligned, or aligned with the alignment included in the size.

This sounds like a spec that grew organically, with multiple people contributing to it over the years; the alignment might've come from PowerPC/68k-based Macs, as also evidenced by the use of big-endianness throughout.