The video on the Martha Stewart recipe page, though it's not Martha herself, is *amazing*.
Specifically: it goes through how to separately change the recipe for soft-and-chewy cookies versus thin crispy cookies versus cake-y cookies.
And just randomly, as a side note, he mentions something I've wondered forever: what's the important difference between baking soda and baking powder?
So, for the record? I totally approve of this "kitchen conundrums" guy. And his baking soda versus baking powder advice actually tells me something I hadn't already known, but stumbled on, for my whoah-they're-airy snickerdoodle recipe.
Also that he tells you to use "two teaspoons of the very *best* vanilla extract", while clearly pouring way more than two teaspoons straight from the bottle. This is a man who knows what he's doing.