Martek v. Nutrinova presents an interesting case for the burgeoning lexicographer. The term at issue is "animal" and the question is whether or not Humans are covered by said term. The majority held that an applicant, when they have not expressly defined limits to a term (i.e. animals = all animals -humans and kittens), there is no inherent exclusion to members of the term. (If you claim "Rock Bands" then "Creed" is coverd by that disclosure. Arguments before the CAFC that "Creed is christian Rock, Not rock rock" will get you nowhere, since you never limited Rock Bands to "good rock bands").
The majority goes on to point out that regardless of if the preferred embodiments in the specification appear to limit the definition, preferred embodiments are just subsections that have been highlighted for the overall disclosure, and not limiting on the overall specification.
Judge Rader dissents, finding that the totality of the specification should be used to determine if there is a inherent limitation in the lexicographer's definition. Specifically, the usage of the term "raised" with respect to animal made it so the term animal could never apply to people.
Brief aside: Rader here is making a moral / western civilization post modern argument that would not exist 200 years ago. While it is true that Humans are not raised (in the same manner as livestock) at the moment, it was not always the case. The Chattel Slavery system was designed to treat people as live stock, and it is possible that this specific invention would have been useful to someone who wanted to raise Omega-3 intensive individuals. While I agree with Rader's assertions that the term raised makes the definition of Human suspect, I am not a huge fan of using moral arguments to craft borders on the term.
Regardless of the whether Rader and the dissent is correct, the case provides a helpful bit of practical drafting guidelines. It makes sense, if you are going to be you own lexicographer, to put the broadest definition possible in your specification. However, if the broad reading needs some specific tweaking, that tweaking should be done in the preferred embodiments, and not in the general specification. In Martek's case, the reference to raised animals could have been placed in a preferred embodiment clause that spoke directly to the raising of animals. In this way the argument would not have rested on if "raised" modified "animal", but if perferred embodiments can limit general disclosurs. (one is settled law, and one was up for interpertation).
I have often remarked that I draft applications starting with the specification, but always draft the preferred embodiments last. Doing it this way, it is possible to pick out some of the areas that are going to give you problems down with the Examiner, and hopefully shore them up.