It is actually true that one can get a GC in less than 6 months. I am a prime example for that. I got married last year while I was in second year Medical School and my wife was in second year medical school as well. I started my process in April and I had my GC in July 17 th. It is Possible, I don't know if it is due to through marriage or not but I think if you have all of your documents in right order and right way you can get GC in no time. The good thing about that was I didnot have any lawyer either.