Catan Cheats

I stumbled across a glitch to get the Villager (earn 25 victory points), Citizen (earn 100 VP), and Elder (earn 250 VP) achievements very easily. When you are placing your second settlement at the start of a new game, first place it and then select undo. Keep doing this over and over until you get all of the solo VP achievements. Apparently every time you place the settlement the score is added to your running total, but when you undo the action it never gets subtracted.