Going back to the original question...
It needs the timed fuse() from a Bomb role and a non-lethal explode() from a
Spouse role, though each role provides both methods.
1) How often do you in real life find yourself needing to do things like
this in real life? This is a sort of strained, if amusing, example. :-)
2) A lot of me wonders if a need to exclude a method from a role is a
hint that the role does too many things and should be decomposed into
smaller pieces, such that it can be applied in a more "granular" way?
I'm curious to hear the experiences of Ovid and others working with
roles a lot too. Is this a serious lacking in Perl 6's roles as
currently specified, or something that, in being absent, makes people
consider their design more? Knowing that will influence the solution we
choose, which has options ranging from, "yes, make a neat syntax for it"
through "leave it out of the core, and if people want it enough it can
be a CPAN module".