This level was, if I remember correctly, of only medium difficulty to me, personally, when I ran through the Havoc set. Then again, maybe it was just because Havoc 4 was VERY hard for me, and I figured out the main trick to this level via the "There's really no other ways I can think of that work" method, and the second part was just an extension of it.
That said, I love the trick used. You'll see it a couple times (In a varient form) in my upcoming to be eventually released Cheapo packs.