I voted never. I haven't taken a position on this yet, but at this point I think I am ready to do so. While I think that there will be many short-lived short squeezes over the next several years, I think that the mythical day-of-reckoning that people talk about on the investor threads here is just that, a myth.
I think that there are lots of different kinds of shorts playing with TSLA, no single event will make them all bail, just like no single event would make all the longs sell. Furthermore, just like when TSLA sells off hard, new buyers come in and take advantage of the fire-sale, when the stock price spikes (say, when a short squeeze starts) new shorts will jump on the higher prices by opening new short positions, and existing shorts will simply double down.
For this, and many other reasons, I think that what we will see is an orderly decline in the percentage of shares that are sold short as Tesla's success becomes more and more certain. There will certainly be spikes, squeezes, but nothing like people here are looking for.
Don't get me wrong, I hope that I'm wrong and that we see whole hedge funds go bankrupt because they shorted TSLA; but at this point, I think I know this stock well enough to take a position, and I'm going to say it doesn't go down that way.