Unlike a yard of ale, which would be seriously concerning if it was a cubic yard*.

Weight/volume conversions are all challenging. I recall when I discovered that US cooking was mainly done by volume instead of by weight, I found that such an odd concept. I now, incidentally, generally think it works really well - but did have to be convinced by a process of actually cooking.

* My wife informs me that she's never heard of this, which means I suppose that you might not have heard of this, thus: http://en.wikipedia.org/wiki/Yard_of_ale