Some Fuzzy Logic

As the count down continues for the release of results re SIRFLOX the question is how much speculation on a good result has been built into the current share price.
My back of a fag packet calculation says the following:
1) Half year results released on the 18th Feb
2) Share price jumped to c $34 (closed a tad below but lets keep it simple)
3) Lets assume market finally got it right. Re $34 for the expected growth in sales and margins (base case).
4) Aus $ was average 90c (web broadcast 25th Feb)
5) Lets assume average $ now 77c
6) Circa 75% sales in US $
7) 13c/90c by 75% says result should increase by 10.8% just via exchange rate alone (I said this was done on the back of a fag packet!!)
8) $34 by 110.8 = 37.67
9) So current price $39.30 less $37.67 says expectation in SP is $1.63 or about 4% of the current SP.

The question is therefore is it worth getting out now for a 4% speculation price premium?

I am no longer a huge risk taker but I also don’t mind taking a punt when the odds favour me. Everything about the SIRFLOX study is about how large the benefit will be – not if there is a benefit. For me its worth the punt – the upside far outweighs the current base case performance. Guess time will tell – it always does.