This use case was always possible, and has already been standardized at the ietf in RFC 6920 for a decade.  Blossom doesnt really standarize it, imho.  It proposes an api which pollutes the namespace, and wont fly in certain deployment scenarios.  But it is a system that works, and could perhaps be future-proofed with the use of reverse proxies.  I wouldnt get too wedded to the system tho.  There is sufficient technical debt that further iterations will be needed, imho.