That's a great question!
I'm a yacht chef which by nature might be both the easiest and most difficult chef's job ever. It's easy because most people don't want to eat restaurant style food all the time. It doesn't matter how rich someone is; they most ultra wealthy people want a baked potato with a grilled New York Strip, a turkey sandwich or even a pb&j with Ruffles Potato chips on the side. (I'd serve it on a paper towel, but that might be going to far.)
It's also one of the most difficult jobs cooking ever. You try braking down a chicken in six foot seas! I'm at sea hoping from paradise Island to paradise Island everyday. Great. Except when I need to buy something, then I have to wait a week. Not like in a restaurant when you send the busboy to the market to get lemons or something.
It's so important to have recipes that work under the most trying circumstances. Cooking on a yacht is a three dimensional experience. Problems arise that no land based chef would ever worry about. Often the yacht moves at the guests whim, so I rarely know where or under what conditions I'll be cooking dinner.
Having recipes that always work that are simple and appeal to American sensibilities is key to my survival as a yacht chef. I also cook for the same people. Unlike a restaurant that over time perfects a menu with only thirty or so recipes and a handful of rotating specials, I'm expect to keep coming up with new and interesting ideas that are American. All my recipes are fine dining French, which is great if I want to have the best fine dining restaurant in town, they just don't work on a boat.
The Joy of Cooking is a brilliant cookbook. Every recipe works. Have you ever followed a recipe that didn't work? What a drag? People pay me a ton of money and the recipes I make have to work each and every time flawlessly. The problem with the Joy of Cooking is that the quality after following the recipes exactly to the word is mediocre. They are ok, they always work, but they are ok and not very inspired.
Every single recipe in Cook's Illustrated cookbooks works every time, without failing, under pressure. I can count on them. I know I can try new things that I don't need to work on to perfect. Everything comes out great if not perfect every time. If I need to make a quiche, bam it's there. If I need to make creamed spinach to put under my egg over easy with the truffle oil and shaved black truffles, bam it's there. If I need a either a creme brulee, creme caramel, flan, custard, souffle or a chocolate ganash, I'm there.
I would recommend them to everybody who is interested in American food and American interpretations of French, Italian, Spanish and Pad Thai.
Here is a cookbook I made for friends and family as a Christmas present. I swear 70% of the recipes I just copied out of Cook's Illistrated. http://www.thechefsgalley.com/assets...y-yachting.pdf