I frequently read answers from a 5k rep user who obviously knows his stuff, but their answers are nearly unreadable because of a lack of punctuation, no paragraph breaks, and run-on sentences.
I have occasionally fixed these problems myself via edits, but many times I start editing and just give up because of the amount of effort it takes.
How can I bring this to their attention gracefully?
If you'd like to bring it up to a user, try posting a comment or two. Not everybody here is a "computer person", so they just might not understand how grammar/formatting can improve their posts, or how to use the interface/markup. Just make sure the comment is polite, helpful, and respectful. You can even include a link to this question in the comment, so the discussion can take place away from the main site.
If you want to approach the person in a less "public" place, try summoning them to chat.
Remember, we're not all English majors (or even native English speakers), so grammar and punctuation may not be as easy for us all.
Some people just don't feel that formatting matters. I'm not sure where this movement started, but I've gotten pushback from users who refuse to format their posts. They feel that only content is important, and grammar/formatting is wasted time. There's likely not much you can do about these users, aside from formatting their posts for them.
A "great answer" has both great content and is easily understood.
an answer which is a giant meandering run on compound sentence spewing occasional nonsense with no punctuation questionable structure disregard for readable capitalization spelled like a grade school student that is often spelling like how words are pronounced in the ghetto rather than how they should be spelled ie than versus then or would of versus would have is something which makes it not a great answer but only a mediocre answer someone desperate might dig a useful answer out of :-)
I have done some cleaning up along those lines. So far as I know, none of those authors seems to have minded the clean up.
Unless I'm feeling the disease (aka, wasting too much time here; must apply now to be delving into meta) I select from the options:
If, as purported in the SE model, good answers get upvoted and bad answers don't (I try to hold downvotes to WRONG answers, for the most part,) this leaves the door open for someone else to write a coherent answer, or for someone to edit the answer after which it can be upvoted. While I may know it's wrong, and how to put it right, it's not my job, and choosing not to do a thing that's on a basis of unrewarded volunteer activity is not something you should feel guilt over, IMHO.
While I have spent some (diseased) time plowing though the review queues in the past, I rarely bother of late; it doesn't bother me, and it reduces the time-suck this place can be. If that reviewer badge means a lot to you, be my guest - if you're newly empowered and enjoying the novelty, be my guest.
I am also hesitant to dive too heavily into editing stuff where I may be laying what I think the person meant onto what they scribbled, to the point that an edit may change the meaning. I've certainly encountered a few cases where a review of the edit history showed that this had already happened with someone else in the editing seat, either changing the meaning, or making a lucid, comprehensible original question/answer incomprehensible. Teasing out the meaning of something poorly written with no direct knowledge of what was actually meant can be tricky, especially if the writing is really poor.
I will now resist the urge to remove all punctuation and formatting from this post, and add some deliberate misspellings and correctly spelled wrong words to the ones that got past me anyway.
