After a conversation in #perl6-dev[^1], I'm rejecting this ticket. Unlike invisible operators (RT#128159), there's no security risk involved. Unlike `&0` (RT#128159), there's no ambiguity in what the non-throwing behaviour is supposed to be. This is just a peculiar intersection of two very-well defined rules and there does not appear to be a sufficient reason to mangle those rules with special cases, all for the sake of banning this intersection.
[1] https://irclog.perlgeek.de/perl6-dev/2017-06-08#i_14703885
