I tried carrot and celery more than once in my pasta sauce and have always come back to not including it, just because for me it's tastier without them. That said, i have decided my bolognese is close enough to what is obviously a good one .. https://kitchenswagger.com/rigatoni-bolognese-recipe/ .. to be called bolognese. Mine is basically the same without the two ingredients mentioned. Just wish i could spell it bolognaise 'cuz that's the way i spelt it for years.