That’s essentially my picture, although I like to paint with a somewhat finer brush.
If that's your thesis, it's a lot simpler to just short a high-flying stock like CELG than gamble on whether or not Ariad's pipeline is going to be successful or not.
The other risk with shorting Ariad is this is a stock that could be bought at any moment (which I would not be pleased about if it happened). If you look around the oncology space for companies with high-class unpartnered drugs and low spend you will only find a handful.