Yes, I feel this aspect of RP is so important that it deserves its own thread. This has been an issue on both ends of the spectrum at some point of another on this site, as well as every other site I've been to.
So... what is readability?
Readability is the efficient use of space in a story to deliver the whole story with effect and purpose while still maintaining a reader's attention. It is an easy read that ultimately results from one's style. It is affected by four factors: Content, Style, Design, and Structure. The number of syllables to a word and total syllable count to a sentence can affect this. The number of sentences in a paragraph can affect this. The familiarity of a reader with words and taking into account the attention span of the target audience is also a factor that affects this concept.
The READABILITY of your application and your posts is a very, very important issue. A short background and RP Sample will not get your character much in the way of power or respect. A tedious, stiflingly long background that goes into every unnecessary detail you can possibly think of, however, will yield the exact same result. No one who knows what good writing looks like will want to read something with several paragraphs that are twenty sentences long. I love long profiles, but even I refuse to read something like that because it won't be worth my time. Most of the extremely long paragraphs I have seen in my time have had the potential to be cut into a third of their length.
When we grade an application, what we are looking for is mainly READABILITY. I tend to write very long Background sections, but I make sure they flow logically and with purpose toward a particular goal. I throw in humor, plot elements, obstacles, plot twists, etc. that keep things dynamic. In a paragraph-style RP Site, keeping a reader's attention is paramount, or no one wll want to post with your character or even deal with you.
If you read any of my posts or Character Application, you will find that I do not take multiple ten-sentence long paragraphs to describe the look of my character's face. I do not spend multiple twelve-sentence long paragraphs describing my character's shirt and pants. I do not devote multiple fifteen-sentence long paragraphs regarding how my looks when she's pregnant and how it feels to touch.
Going into too much depth is a killer blow for any type of writing and, quite frankly, will draw my objections to any form of HL or VHL ranking. The reason I would object is because it's an immature and obnoxious style that drowns the relevant details in a sea of irrelevant details. Your reader literally GETS LOST, and when people get lost they generally stop reading or skip entire sections that may actually contain important information.
Too little depth is never good - some might even call it the worst possibility of writing. Well, if too little depth is the worst, too much certainly comes at a VERY close second. We base rankings on length AND readability. If it's not a good read, it's not going to get a good score.