This is for those Reading Comprehension gurus, I am trying

I'm happy to give my 2 cents here.

What you ask is really a fantastic question. Reading intelligent material is one of the best ways to prepare for GMAT RC, and in particular, The Economist is an exceptionally intelligent weekly that will expose you to all kinds of issues germane to the business world. (The knowledge & perspectives you glean from The Economist may well help you in your AWA essays as well!)

Here's what I would say about reading articles in The Economist as practice for GMAT RC.

1) Read actively, with paper and pencil. Practice summarizing briefly each paragraph, writing this in shorthand on paper, just as you will write on the notepad on test day.
2) Always summarize for yourself, in ten words or fewer, the main idea of the article, then double check that each paragraph plays a role in supporting that main idea.
3) Practice looking for "signal" words --- although, however, but, nevertheless, etc. etc. ---words that indicate a shift in the direction of the argument
4) Always be asking yourself: is this a neutral perspective, or is the author arguing for or against something? The Economist tends to have a balanced tone and a subtle wry sense of humor, so it's a particularly good source for this, because it doesn't hit you over the head with tone. Exactly what words and phrases in the passage provide the hints as far as tone and the author's perspective?
5) Once you have sorted out the main idea & role of each paragraph, go back to some juicy or memorable detail -- why did the author mention that? How does that detail support the paragraph? How does it support the main idea of the whole passage? (I can guarantee that every single syllable in the The Economist has a specific purpose.)
6) Really advanced --- pick an intriguing article and pretend you are GMAC. Write a set of 3-4 questions on this article. What would be particularly GMAT-like things to ask? You know they will ask for the main idea --- can you come up with tempting-sounding decoys for wrong answer to that question? Can you formulate detail questions? tone questions? etc.

Of course, all this would be much more effective if you were going to read the articles with someone else, or with a study group. Imagine there are four people in a group, and you all agree to read a particular article from The Economist. Let's say you draw from a hat --- one person has to create a main idea question, one has to create a tone question, one has to create a "purpose of the nth paragraph" question, and one has to create a detail question. Each person reads the article and creates his/her assigned question, and then the next time you meet, each person has three other questions to answer. One of the best ways to understand the logic of GMAT questions is to try to write them yourself!

I hope this helps. Please let me know if anyone reading this has any questions about what I've said.

Mike