Here has three posts about the Google high pay adwords, maybe it's useful for us, you can write more posts about these keywords to get more revenue from blog. Keywords part I http://www.hatmoney.com/high-pay-google-adsense-keywords-2007 part II http://www.hatmoney.com/high-pay-google-adsense-keywords-part-ii part III http://www.hatmoney.com/high-pay-google-adsense-keywords-part-iii
Yes it would work if you are already getting lots of traffic or think that you can...I think its a gray area where the terms and conditions are concerned.
you are right, the most important thing for a blog is traffic, but if you get 100 unique visitors every day in average, it will bring more revenue if you write more on these keywords. btw, It's easy to get 100 unique visitors everyday if you really pay more attention on your blog.
Why should we bother to write about things that don't interest us. Not to mention that just because it's a high paying keywords, we will get paid high.
Look at these keywords, insurance is so hot, auto insurance, life insurance, home insurance and so on, we get these questions or information everyday, so I think we can write some experience about it in blog, why not? just experience, but can get more revenue for blog.