Did you test your claim?

corion@aliens:~/parent$ perl -we 'require "t/lib/FileThatOnlyExistsAsP
+MC.pm"'

corion@aliens:~/parent$ perl -we 'require "t/lib/FileThatOnlyExistsAsP
+MC.pm" or die "Uhoh"'

corion@aliens:~/parent$ ls -l t/lib/FileThatOnlyExistsAsPMC.pmc
-rwxr-xr-x 2 corion corion 82 2007-08-02 22:57 t/lib/FileThatOnlyExist
+sAsPMC.pmc

corion@aliens:~/parent$ cat t/lib/FileThatOnlyExistsAsPMC.pmc
package FileThatOnlyExistsAsPMC;

sub exclaim { "I CAN FROM " . __PACKAGE__ }

1;
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