My thanks to Kris and Moritz for reassuring me that the Perl 6 initialization semantics remain sane. :-)
In response to yary's original observations, the extra work required to achieve non-standard semantics doesn't seem unreasonable to me. Especially as, should one need to do it regularly, one could just create a role (possibly parametric) to handle all the boilerplate and then mix just it into any class that requires it. Damian