Actualy {blah, "blah"} is considered a block. See below for proof. ;). Perl is trying to be smart and guessing on what exactly {} is based on context. {} makes lots of since as a hash ref but very little as a block. {blah, "blah"}is usefull as a block while my $x = {blah, "blah"}; is most probalby a hashref and treated that way.

C:\Perl\test>perl -e"{test,'blah'} print 'hello'";
hello
C:\Perl\test>perl -e"{test,'blah', print '1'} print 'hello'";
1hello
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