Writing: Copy a bestseller to be a bestseller!

I read recently in my Brainstormer writing book that when you start writing, you should take a book - in the genre you're wring in - and copy it out word for word.

What!?

This didn't make any sense but what he said next did... Why you should do this - maybe not the whole book but parts:

1) You practice writing proper grammar and punctuation. Need help punctuating dialog? Copy a master writer!
2) From copying chapters, you learn what length chapters should be, you learn story structure and proper narration.
3) You pick up tips on writing action and dialog or any areas you may be weak.
4) Writers have to choose their words carefully. Anyone can eventually explain their novel in 500,000 words but most publishers will want less then 100,000 so you need to value each words you pick. By copying a best-seller, you see how every word chosen serves a purpose. You don't waste your time or your words.

Now, don't actually try to sell your copied novel... that's called plagiarism. But, as you copy, take notes and write the lessons you learned. Ask yourself why the writer chose to write this way or pick the words he did.