Hey like i said i worked at a recruiting company for a few months so I can definitely tell you that it is not a bad thing at all. In fact it really really helps. That is why alot jobs (and recruiting companies) ask you for references all the time and we call your previous employers to learn more about you, which has the same affect as your letter of recommendation. It lets us know that you didnt leave on bad terms, didnt burn any bridges, no red flags, etc etc. so by all means include it