I've actually been using a set very similar to this with different EVs (which I am still playing with) since about May/June (when I was in my slap Draco on everything phase), but its really unstable and needs someone with the know how to operate it.
Random EVs that I don't feel like digging out
-Dragon Dance
-Earthquake
-Draco Meteor
-Fire Blast
I gave it enough speed (300) to outspeed other neutral Salamences, and it can 2hko Blissey after 1 DD, the Speed boost then lets it take on other Pokemon that Salamence normally wouldn't want to, like Weavile and Garchomp. It suits my style of play which is reckless and aggressive, but I don't think this is the end all of Pokemon sets, it doesn't touch Cresselia, and several drops will ruin it. But I have been using it in the beginning of the game for quick damage with Draco and endgame sweeping, both of which it has been great at. Its not a stable set and by no means should be used by someone uncomfortable with it, Specsmence and DDmence do their jobs much better, this just combines the best of both worlds to cause the opponent to panic and figure out whats going on before something even more terrible happens.
The second move (Earthquake) leaves it open to some problems, this Mence has moveset syndrome and could benefit from an extra move, Crunch, Brick Break, Aerial Ace, Earthquake all do great damage to some things but then leave you open to other things (which can be counter by other teammates), which is why the DDDracoMence isn't the end all of Pokemon sets.