C:/> perl unit2summary.pl < dmp4.piped

Can I take it from the prompt shown in your command line that you are using some other shell than cmd.exe?

If so, try your commands with cmd.exe. I can't see any difference in the behaviour here:

C:\test>perl -pe1 junk.dat | perl unit2summary.pl
PASSED: mc creation
FAILED: mc attr

TESTS: 2   PASSED: 1 (50%)  FAILED: 1 (50%)

C:\test>perl unit2summary.pl <junk.dat
PASSED: mc creation
FAILED: mc attr

TESTS: 2   PASSED: 1 (50%)  FAILED: 1 (50%)
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