Quote Originally Posted by biondino
One mistake above - if you bet twice the pot your opponent needs to invest 2/3 of the pot, not 2/5.

i.e. pot is $5, you bet $10, oppo is now having to bet $10 into a $15 pot.
Nope, he has to invest $10 into what will be a $25 pot, so 2/5.
One other thing here - you are ignoring the possibility that YOU will improve your hand. Clearly there is a difference between having AK on an A27 flop (5 outs to trips/two pair) and AK clubs on a AQJ 2-club flop (4 outs to straight and 9 outs to flush on top of trips/TP draw).
I let the odds that you or your opponent improve their hands cancel each-other out, for two reasons:
1- they should be roughly equal
2- we are using estimates anyway, with a variance of 1-2%, so decimal odds don't matter too much here.