TTreeProcessorMT leaves implicit multi-threading enabled after a call to Process

When TThreadExecutor creates the IMT thread pool (as opposed to when the thread pool is explicitly created by users via ROOT::EnableImplicitMT), it deletes it at destruction time:

{

  TThreadExecutor p(3);

  std::cout << ROOT::ImplicitMTPoolSize() << std::endl; // prints 3

}

 std::cout << ROOT::ImplicitMTPoolSize() << std::endl; // prints 0

The same cannot be said for TTreeProcessorMT, although the two classes should have consistent behavior:

      ROOT::TTreeProcessorMT proc("f.root", "t");

      std::cout << ROOT::GetImplicitMTPoolSize() << std::endl; // prints n_cores 

      proc.Process([](TTreeReader &) { });

   }

   std::cout << ROOT::GetImplicitMTPoolSize() << std::endl; // still prints n_cores!!

This looks like a total accident: TTreeProcessorMT::Process makes use of TParTreeProcessingRAII, the constructor of which calls ROOT::EnableImplicitMT() (with no arguments) and the destructor of which never calls ROOT::DisableImplicitMT().

I don't think this is the desired behavior, but I'd like to hear other opinions. Also, I don't know how to fix it, I am not familiar with how TParTreeProcessingRAII is expected to behave.