Is it really so easy to fix Devel::ptkdb to support lvalue sub's? (rfce)

I have to use a Perl Lib that use lvalue subs. For debugging I use since years Devel::ptkdb.

While debugging the Devel::ptkdb die with the message:

can't modify non-lvalue subroutine call

So I start to investigate that problem and for now the resolution is add following sub to Devel::ptkdb (v1.1091):

sub lsub :lvalue {
  local $DB::single = 0;

  no strict;
  return &$DB::sub;
}

I also learned that my knowledge about TK and the Perl debugger internals are not deep enough to prove that this change does not have side effects so this is a request for code evaluation.