Some interesting info found re: alfredo sauce.
"The original owner of Alfredo's Restaurant in Rome, Alfredo Di Lelio, is said to be the originator of this delicious but rich dish of worldwide fame(invented at Alfredo alla Scrofa). He has since passed away, and the recipe for both the fettuccine pasta and the sauce remain secret. Some say the creaminess and lightness of the fettuccine and/or the sauce was in the cheese he used, or the addition of a little olive oil to the preparation of the fettuccine, others that the fettuccine was cooked in milk, still others that he gave each dish his blessing with a final toss using his gold fork and spoon before sending it to table."
The quality and taste of the ingredients is the key to success with fettuccine Alfredo - especially the fettuccine and the cheese. The fettuccine should either be freshly made and as thin as possible, or, if store bought, the best fresh (not dry), thinnest pasta you can buy.