I am properly chastened -- I do have a tendency to forget checking for failures, which is really very bad.

This is a slick way to check problems with tr, and still leaves me scratching my head: I checked my $wrong and $right strings and they contained no / (surprise) but using the packed characters produces a different result than using the octal "names", and only when using tr/// -- not when printing them out to check or using them in a s///g construction.

I must do further investigation.