Yup. Not too difficult since the charts are littered with them and 75-80% turn out to be bearish patterns to make more satoshis from

Thomas Bulkowski disagrees.
This is what his backtesting says:Breakout: Can be in any direction but is upward 53% of the time.
If price rises into the pattern it breaks out upward 63% of the time.
In a vacuum, I'm really not sure about upward/downward bias. I've never backtested this pattern myself. I have noticed however, that they (like all triangles) are often continuation patterns.