The avoidance of reduction is for optimization purposes. The .norm stuff is fixed now in https://github.com/rakudo/rakudo/commit/aac9efcbda and tested in https://github.com/perl6/roast/commit/7d0daf5286
However, there's a data-race in Rational.REDUCE-ME and it needs to go: https://irclog.perlgeek.de/perl6-dev/2017-02-13#i_14093035 Renaming the ticket to that.
