At the same time it is real - you are there using every sense that you possess.
As a guest in the author's house, you sweat, your muscles ache and you get dusty as the rennovations take shape. You want to soak in a long hot bath after reading several pages.
You shop side by side with her at the market, smelling, hearing, touching and tasting all that Italy has to offer.
At her table you do not feel compelled to go to the fridge for a snack, but feel completely stuffed, like you have really eaten the meals she has described.
What a wonderful place to lose your self, but Under the Tuscan Sun.