How do you "break-in" your coils?
When I mount up a new BVC for the Nauty Mini, I put two drops of e-liquid down the coil pipe and let it soak for a minute before screwing it onto a filled tank. Then I'll set the tank upright for a couple minutes to make sure the wick ports get saturated too.
I then set low wattage (7-8W) when firing for the first few times, making sure to keep the wick primed (a little suction, without firing, at the beginning and end of the draw).
After that, I'll start ramping watt by watt until I get where I want. I'm using a VaporShark rDNA30, and I just put a new BVC coil in tonight. It's now humming away quite happily at 14.8W (vaping ITCVapes' Custard #3, 50/50 12mg). A 2-second firing gets me a nice juicy mouthful (I'm not chasing clouds, obviously), with an extra second of suction after releasing the button.
If you're still burning up coils under these circumstances, there might be a problem with your iStick. They're known to fire a little hotter than other mods, due to a difference in power modulation. It shouldn't be enough to wreck your coil at 11W, though...unless something defective is going on.