Note for doko/barry: The multiarch/Tuples page should have a section on how the MultiArch Tuples interact with hwcaps (or a link to such a section in a different document).  The rationale for not using Gnu-Triplets in MulitArch/Tuples currently says that we do not want separate entries for (as an example) i386 vs i686 instructions but does not tell why.

https://wiki.debian.org/Multiarch/TheCaseForMultiarch#Mixed_ABIs_and_instruction_set_extensions  says that the i386 vs i686 use case is probably better addressed by glibc's hwcaps but points back to MultiArch/Tuples for rationale.

A section of rationale and example to show how the multiarch tuple and hwcaps complement each other would fix that.