Hi Oldnemesis,
I am a bit confused by the way how you calculate the expectation for your trades. In APPL's case, shouldn't be like this:
Expectation = 0.91 x 26 + 0.04 x (-474) + 0.05 x ((26 - 474) /2) = -6.5
Also, in a previous post you mentioned that you are getting the probability numbers...