for ([0,0], [0,1], [1,0], [1,1]) {
  my ($phys_clump, $mutate_orig) = @$_;
  my $orig = zeroes 3,2,1;
  my $clump = $orig->clump(1,2);
  $clump->make_physvaffine if $phys_clump;
  ($mutate_orig ? $orig : $clump) .= 3;
  my $got = $orig->unpdl;
  is_deeply $got, [[[(3)x3],[(3)x3]]], "phys_clump=$phys_clump mutate_orig=$mutate_orig orig" or diag explain $got;
  $got = $clump->unpdl;
  is_deeply $got, [[(3)x3],[(3)x3]], "phys_clump=$phys_clump mutate_orig=$mutate_orig clump" or diag explain $got;
  $got = $clump->uniqvec->unpdl;
  is_deeply $got, [[(3)x3]], "phys_clump=$phys_clump mutate_orig=$mutate_orig uniqvec" or diag explain $got;
}