Quote from Jerkstore:
Backtesting for an idea like this is problematic at best. This is an interesting idea, but I am not sold.
We are discussing a low reward, high risk, high % bet. The expected return of the leveraged etf stays the same as the volatility of the underlying goes higher, while the median return goes lower. This implies a different distribution of returns, not a lower expected return. That means if the stars align properly, your double and ultra ETF can really take off higher (particularly the double and triple shorts). These double and triple short ETF's can easily go hard to borrow at the same time, just like SKF did back in March 2009. First I would trade this strategy using strict stop losses. I would also suggest buying an upside call to help hedge the trend risk. However, the teeny calls in the leveraged etf's are juiced up due to this very phenomenon. This would naturally somewhat eliminate the "decay" returns you are after.
I have not looked at this idea in over two years when I was running numbers on some of the trades that could be done with the contango with the oil ETFs.
I would guess the quants have this figured out to the hundredth or less of a penny but couldn't options be used with this concept to further the time decay as well as protect from having your short called away? I would guess there is some sweet spot with a month and in the money option pair that may get you there.