I think the computer is not relaying on bad play from the opposition but more that if you as north assume that east has all the remaining points you can do it with a bit of luck.
So you get a lead of QH take it in north then lead a small spade to the KS as east has the AS, if they play the ace easy if they play the JS then you just have to hope when you go back into north's hand via a diamond that the ace falls and it does. Then you make.
I know this is a gamble to say the least but I think that is the line of play the computer was suggesting.
Edit: Thinking about it further one could say that after the second round of diamonds you should try this. You will be in north's hand. When the JS goes up you can think second hand play low right? so unless they have the 10S as well in which case you will never make, might as well try for the AS drop on the second round.