learning that the form $var->{key}{key} is legit.

It is legit, but I wonder how many monks use it. I personally like the -> and I always write $var->{foo}->{bar}. I find it aesthetically pleasant as well as a good reminder of the fact that $var->{foo} is a reference and not a hash.

I guess I am not the only one, given the overwhelmingly negative reaction to the replacement of the arrow by a dot in Perl 6 (which was probably Larry's goal now that I think of it, just to drive the point that Perl 6 is different from Perl 5 and that nothing is sacred).