I've quickly skimmed this thread, but have an overpowering urge to plunge in where angels fear to tread without having carefully considered every word above, always a dangerous proposition for me:

In reply to:

I think that your interpretation of 'pons asinorum' is not quite right. In Dutch, an ezelsbruggetje is a little trick to remember something, in particular by making a connection with something unrelated. For instance, if you have difficulty remembering the difference between stalagmites and stalactites, you might think of mammary analogies and you will never forget that stalactites are the hanging variety.

We need a precise definition of an ezelsbruggetje--even an etymological breakdown. However, whatever kind of bruggetje it is, it appears to be simply a mnemonic device, many of which are used by students in med school. I hope there aren't too many blockheads there.

The bridge [2nd edit: English application] over which we're trying to cross in this thread doesn't seem to be a reference to mnemonic devices at all, but to one that separates the men from the boys, the mice from the men, the wannabes from the genuine items... This bridge is the proverbial acid test of mental ability in specific fields of mental prowess. I couldn't cross this bridge when I encountered the Great Bridge of Calculus. The mule in my brain refused to cross. I mean, that mule sat flat down permanently. That rascal didn't like the looks of the Great Bridge, thought reading Thomas Hardy was much more engaging (circa 1969), and had an insurmountable desire to learn to play a once-retired Handel chaconne. Who was I to argue with the mule?

Edit: Yep, I should have read more carefully. jheem did offer us the etymological breakdown. So, I'm back where I started when first reading tsuwm's thread starter. The phrase means two things to two groups of people at the very least, and I would want to argue that in the German/Dutch sense what would appear to be a tool of fools is actually a very useful bridge. Who cares if it goes by the name Asses' Bridge?