Just because Xur is supposedly random, doesn't mean that Bungie can't re-roll his inventory (read: control) until they get a combination they are comfortable with (or roll more than one combination to choose from). There is a reason why Universal Remote (never before sold) and Red Death (hasn't been sold since the first few weeks) just "randomly" showed up after the shotgun and pulse rifle buff. That's a little too coincidental for me to believe Bungie doesn't have any say in what gets sold each week.