I was thinking the same, it looks like an impossible thing to be seen in the near future. To get the same exact number twice in a row has so low chance but I have just got it on other site. At first I cant believe it but it was real that I roll the same number in a row as shown in this screenshot http://prntscr.com/gqdlj9

with above experience, I'm starting to think that the jackpot on PD will be hit sooner as long as the players notice that they hit 77.77 in a row which is the hardest part because they should keep on watching the rolled number.