Strange
perhaps it depends on the length of the input string?
My attempt shows a different result
You seem to be under windows - so just for comparison: 
$ cat a.pl; echo '-----------' ;echo;./a.pl 
#!/usr/local/bin/perl -w
           use Benchmark qw(:all) ;

our $s = join ' ', 'aa'..'zz';;
cmpthese( -3, { 
    split => q[ $_=$s; my $n = @{[ split ]}; ], 
    regex => q[ $_=$s; my $n = () = /\S+/g;  ] 
});

-----------

        Rate regex split
regex  981/s    --  -53%
split 2098/s  114%    --

[download]

Hm, now where's the big diff to the other Bench?
I.

In reply to Re^4: Counting the number of items returned by split without using a named array by Anonymous Monk
in thread Counting the number of items returned by split without using a named array by Anonymous Monk

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