I really can't answer how bad it will be because I will not be the one reading your essay. I would think that it matters on how good of a day the person who's reading your essay is having that day or how good your numbers are. This is just a logical comment, but I would think that if I would have a bad day and didn't feel like reading any essays and then would have to figure out where the paragraphs start and end on each essay, I would be a bit upset. Also, I would think logically, that if you have good numbers the person would be a bit more patient and try to read your "block" essay rather than the person with a similar essay and average numbers. Remember, sometimes these people don't even read your essay. Eventhough the say that they look at every application from beginning to end, but logically if you think about it, that would take a very long time. So, if you already sent it out, just relax. There is nothing you can do about it not. Just hope that you essay is easy to read and not that hard to figure out the location of each paragraph.
Good luck,
dmitri