No, not once. I have all the coils I have used in this prolonged process and they are all reusable in my opinion. This is the only reason why I'm not thinking it's a resistance problem. The only thing I could think of would be if something were to shift and either slide to a partial 510 connection and perhaps that could consider it a short? Or if something were to shift and touch the retaining ring that is over the above shown part.the post should be exactly center with the cap that the retaining ring screws in to, right? so maybe by some oddball chance it moves? I have no idea. If you have the clone or one of the Ithakas that the post is uncentered, how did you go about fixing this?
P.S. The one time it has shorted after I have been rolling, it has been while I was stationary.. The other time I was rolling and it worked up until I cleaned out the remnants of the eliquid and refilled a new flavor, then it kaput.