I respect your preference, so I will try to respond with some colloquial form of reasoning. Please forgive the slight abuse of information theory...in general,

I respect your preference, so I will try to respond with some colloquial form of reasoning. Please forgive the slight abuse of information theory...in general, styled text will have lower entropy than the same un-styled text. Low-entropy text will be more memorable than high-entropy text because it contains more information. It's like a chapter heading in a book - not only is it interesting and informative, the style provides the context that it is a heading and not the first sentence. Re-reading my previous comment, one could misconstrue that my editor looks like a crayon box. It doesn't. I use fairly subtle styles for most parts of the text, with only a select few items in bold or bright styles (keywords, constants). It helps to skews the distribution of what grabs my attention and what does not.