It could be that BTC remains above the trendline for long, like it did for 17 months in late 2010 gaining a maximum of 80x ($32) the trend breakpoint ($0.4) before declining back below trend at $5 (12x break above line). [Approximate figures taken from the chart, don't unfortunately have quick access to real value points]
I suspect that the bigger the pool of btc holders, the harder it is for the spot price to stay far from the trend line for as long. So over time the spot price line will tend to straighten and follow the trend line more closely.
The other thing that occurs to me is that the price can still crash and stay higher than the trend line, if it started far enough above it.