It's not. If you're dealing with competent enemies you'll get 1 kill and then shot in the face. You're extremely static, it doesn't help the LMG player in the long run and it only helps to aggravate others by the sheer excess of players lying prone for this reason. They get a few "nuisance" kills like this and that's it. The plethora of people actually racking up kills with an LMG are dancing around with a KE7. It's an idea that sounds good on paper but it really isn't, they should've thought of other means to make support more interesting.