It should be noted that grep(/11/||/are/,@text) will be quite a bit faster in execution than grep(/11|are/),@text) because of the short circuit and constant regexpes.

Indeed, after a quick test I found:

#!/usr/bin/perl
use Benchmark qw(timethese cmpthese);

my @seed = ("Hi there 11", "Fred blamed me", "17 o clock", "It's snowi
+ng hampsters", "Pickles are
people too!");
@text = map {@seed[$_ % $#seed+1]}(0 .. 300);

cmpthese -1 => {
        short_circuit   => 'grep(/11/||/are/,@text)',
        alternate       => 'grep(/11|are/,@text)',
}
__END__

bagelbox:~ josh$ perl testgrep
                Rate     alternate short_circuit
alternate      642/s            --          -81%
short_circuit 3309/s          416%            --
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