Why this maybe true at some schools, but the PhD program in the history of art at the University of Victoria prefers students from other colleges and rarely let students from the UVIC MA program into the PhD program. I think people should know that graduate programs vary in what they are looking for. I also read a blog on this site about contacting professors. You should always contact your POI before you apply. That way you can find out if they are taking students, retiring in the near future, etc. Also the professor will remember your name when looking over your app. Of course this advice is for people applying to programs with a small student body.