Gary Lager-great example, I suppose it just comes down to the day...what you feel is the safest thing to do, but as you say, if you can explain yourself and your actions then you are probably making the correct decision. Damned if you damned if you don't!
Not sure I totally agree with alf507ih. Surely what we're all trying to achieve in theses scenarios is the safe conclusion of the flight ie. minimum/no casualties and/or damage. I agree that understanding the problem is one of the biggest parts of the decision making process but is it not the outcome of the problem that we are all interested in ie. what you do about it?