Jon: Oh no! The fat/"chewy stuff" is my favorite part! In fact, I know many-a-foodie that agrees with me and absolutely cherishes the fat. Granted, its all personal preference and I can certainly see how some (or maybe most) don't like it, but I wouldn't be so quick to judge that there's a conspiracy marketing ploy that's keeping butchers from removing the outer flap. I feel its gives a richness and pleasing contrast in texture. Just an opinion - always enjoy your posts.Is the fat the good part? It depends. The fat inside the muscle, called marbling is the good part. It makes the meat juicy and flavorful. But the fat between the muscles is usually surrounded by connective tissue making it chewy.
Just like everything else with food, whether to eat the flap is a matter of taste. Some people LOVE meat so much (for example, my Dad :) that they don't want to waste any of it. What's a little chewiness when it's flavored with lamb?! According to them, it's all good. I am like that with fish. I often find myself eating parts of fish most people wouldn't. But when it comes to meat, I am much pickier. Don't get me wrong. I enjoy meat, but I only want to eat it if it's perfect. Having something stuck in my teeth totally kills the experience for me. As Diana pointed out, there is a way to rescue the flap, trim it, and cook it separately eliminating all the chewiness.
If you are cooking lamb chops (vs a whole rack) and will be browning the eye,I wouldn't mind leaving the flap on. In case you don't want to eat the flap, you can easily remove it without eliminating the parts that are seared (searing is what develops flavor in meat and it would be a shame if the part you are actually going to eat would not be seared). If you do want to eat the flap on individually cooked chops, it will be nicely browned and more fat will render out of it than when the rack is cooked whole making the flap even yummier, if that's your thing.
But if we keep saying that everything in cooking is a matter of taste, we'll never be able to have a real discussion or improve on the final results, so I will stand my ground and say that in a side by side comparative tasting, the trimmed rack of lamb would win. I've never been served a rack of lamb with the flap in an upscale restaurant, so I must not be the only person who thinks it should be trimmed completely when cooked whole.
About the butcher conspiracy -- I am not trying to say there is one. But butcher's are not chefs (at least most of them aren't). And even when it comes to chef's, there are two types: the Jamie Oliver type (easy-going, it's-all-good), and Thomas Keller type (obsessive perfectionism). I tend to lean more towards obsessive perfectionism, so I find chewiness in meat simply unacceptable.
Jo: I NEVER want them to trim it. I much prefer to trim it to my liking. I have taken home far too many cuts that looked great in the case and then when I opened the package after they performed their job it was a disaster.I totally agree with Jo that most butchers don't do a good job, so I never ask them to trim it and normally do it myself. It just so happens that one of the guys who works at Fresh Pond Market (Crosby, though I am not sure about the correct spelling of his name) is really good. He trimmed it perfectly, which was a great surprise to me :)
But that is just my preference.