Switching timethese with cmpthese , here's the math

Win32  ActivePerl 5.6.1 (Build 633)
       Rate  p4  p3  p1  p2
p4 865052/s  -- -1% -1% -4%
p3 876424/s  1%  -- -0% -3%
p1 877193/s  1%  0%  -- -3%
p2 901713/s  4%  3%  3%  --

Win32  ActivePerl 5.8.0 (build 804)

       Rate  p3  p1  p2  p4
p3 831255/s  -- -3% -5% -8%
p1 853971/s  3%  -- -3% -5%
p2 876424/s  5%  3%  -- -3%
p4 900901/s  8%  5%  3%  --

p1 and p3 use the "cut" operator. The optimization depends on your perl version.