wraper,
IMO the problem with analogies is that, while they are extremely powerful for some, there always are people who don't understand the very concept of what an "analogy" actually is -- or even if they superficially know, still have issues in really understanding them.
The most prominent example of this is the so called "Hitler card" or "Godwin's law" phenomenon: no matter how good an analogy someone makes using Hitler (theoretically a very good subject for analogy, since his (simplified) traits are very well known and agreed on), several people totally fail to understand what it means to use an "analogy", and start panicking among these lines: "Oh, the Hitler card is here, now the discussion is over!", or "do you compare that to Hitler?"
To rephrase, your analogy was just fine and actually quite a good one. It isn't 1:1, but analogies never are. Otherwise, they wouldn't be called analogies, they would be, umm, equal things?
I have mostly stopped using analogies because I find about 10% of people totally failing to understand any analogy, or even the concept thereof, on a deep level, and for some reason, these people never say "sorry, didn't quite get it, could you explaing more carefully?", but instead go into the aggressive arguing mode.
For some reason, safety-related threads often end up being a train wreck like this, since people get emotional and stop thinking.