I say this as someone who routinely does get asked to build sites that are (to put it kindly) heavily indebted to other current sites; I can definitely confirm that overlaying text on top of images and making it readable genuinely is quite hard work - especially if your clients are choosing the images! - and these tips are certainly very helpful for those occasions when you can't hire a designer with a natural instinct for making this stuff work.
So, I say: great pair of articles with some great tips.