In a small bowl, combine the chicken and 1/2 teaspoon of the fish sauce. In another bowl, combine the tofu with another 1/2 teaspoon of the fish sauce. In a medium glass or stainless-steel bowl, combine the remaining 5 tablespoons fish sauce with the water, 1 1/2 tablespoons of the lime juice, the vinegar, sugar, salt, and cayenne.
In a pot of boiling, salted water, cook the linguine until done, about 12 minutes. Drain.
Meanwhile, in a wok or large frying pan, heat 1 tablespoon of the oil over moderately high heat. Add the chicken and cook, stirring, until just done, 3 to 4 minutes. Remove. Put another tablespoon of oil in the pan. Add the tofu and cook, stirring, for 2 minutes. Remove. Put the remaining 1 tablespoon oil in the pan, add the garlic and cook, stirring, for 30 seconds.
Add the pasta and the fish-sauce mixture. Cook, stirring, until nearly all the liquid is absorbed, about 3 minutes. Stir in the chicken, tofu, and 1/3 cup peanuts. Remove from the heat. Stir in the remaining 1/2 tablespoon lime juice, the bean sprouts, and half the cilantro. Top with the remaining peanuts and cilantro.
Wine Recommendation: Anything more than a straightforward white with some residual sugar would be pointless with the forceful flavors of the pad thai. A riesling from California or Australia will be fine.