If I recall, the short interest was 40% back when TSLA was in the 30's, so it doesn't seem like it's ever moved all that much. I guess that's why I'm unsure what the value is in knowing the short interest. The theory seems to be that it'd really emphasize a positive stock event over a fairly short duration, but if it was going to have that sort of impact wouldn't we have seen it at some point in the 15 months or so during TSLA's big rise? Seems like the rise and falls, though big, have been over long enough periods of time that the impact of the short interest would have been minimal.
Not trying to argue with anyone, just trying to understand. I've heard repeatedly how some catalyst will be a big deal and we'll see shorts covering, but as you noted the short interest has been fairly steady so even if some are covering it doesn't appear to have much overall impact.
Here's an example with what happened back in April-May of 2013.
Short interest on settled date 4/15/13 (since it takes 3 days to settle, it's reflective of 4/10/13) was 30.7M shares. Stock price was $41.86.
Short interest 6 weeks later (settlement date 5/31/13, reflective of 5/28/13) was 18.6M shares. Stock price was $110.33.
So in just 6 weeks the stock went up 150%. During that time 12M shares sold short covered (in other words, closed out their short position by buying back stock). Short covering was one of the factors that contributed to the huge price increase.