TVIX results using the Dr K Market Direction Model are now posted here: http://www.virtueofselfishinvesting.com/results
Timing Model profit/loss on TVIX (2x VIX) +216.7% since Nov 30, 2010 inception
This was achieved going 100% long TVIX on a sell signal, 100% short TVIX on a buy signal, 100% cash on a neutral signal. Since one may have difficulty getting the borrow to short TVIX, one could buy twice the amount of the 1-times inverse XIV instead.
Note that the volatility is massive in TVIX so position size with care! We discuss possible strategies for trading TVIX here: http://www.virtueofselfishinvesting.com/reports/view/MLR-How-to-play-the-TVIX