You have 350+ posts the last several days expressing or defending your views on this topic. To me, I think you shared a lot of great points worth consideration. Of course some people will remain opposed to your stated views, no matter how many more hours of your life you spend explaining to people on an anonymous forum why their beliefs are foolish.
Exactly why backtesting is useful despite your example. My XIV algo exited just fine as in backtesting there was a clear pattern that (up until that event) was profitable: Exit on 15-20% percent draw down, come back under more specific criteria while hiding in gold and other risk off assets. Since then, there's less of a mispricing of vol. Backtesting IMO is very useful for figuring out when you need to bail because the market has changed beyond what you backtested for. Needless to say I don't believe in algos that will forever work anymore. Of course, had the crash happened outside tradable hours it would have been a bit more problematic for me. Oh yeah, and I mostly hate TA, if you need something from me to be happy.
Just to be clear, I did not claim backtesting is never useful. Nevertheless, thx for your comment!! Backtesting should only be used to reject a strategy, not to predict its success.
Sorry, got lost in the thread. Still in progress of reading the last pages. Clearly a quite sensitive subject given the posting volume.
XIV gave clear warning signs to exit. If hitting fib price and time markers didn't do it breaking first one, then two then three clear support lines should have done it. How can backtesting help any further if clear obvious price points are staring you in the face?
Disagree... XIV had a termination clause. It shut down when it hit a threshold, never to recover. It was designed to fail. The equity indices are designed to increase forever, which means they will never fail, because they do not have a termination clause inherent in them.
So you are saying to hold a long till termination clause takes affect? Don't know about you but I am a trader and not a HODLer. But if I was a HODLer the signs said sell short or exit at minimum longs.
I think what I am saying is...If the XIV never had a termination date, it would be back to normal levels by now. I do not really know how these ETNs work, but if they did not have to shut down...Where would it's price be right now?