I mean, I don't actually believe you that all those levels are polymorphic. :-) IME, we have one, at most two polymorphic fields per message. And for an exampl

I mean, I don't actually believe you that all those levels are polymorphic. :-) IME, we have one, at most two polymorphic fields per message. And for an example chosen deliberately to be annoying, I still like the deeper tree better- at least it advertises that something unusual is going on.