That breaks immediately because &foo is expecting an ARRAY, not an object of class Bar.
In other words, because you're (mis)using ref (which we agreed you shouldn't), you already implement the scheme I suggested. However, there's going to be the user (and it's usually someone like me ... :-) that would assume that since I'm using an array to represent my Bar class, it should fit into either an ARRAY or Bar hole.
It may not be a code issue as much as a documentation issue. That said, there is still an issue. :-)
Being right, does not endow the right to be rude; politeness costs nothing.
Being unknowing, is not the same as being stupid.
Expressing a contrary opinion, whether to the individual or the group, is more often a sign of deeper thought than of cantankerous belligerence.
Do not mistake your goals as the only goals; your opinion as the only opinion; your confidence as correctness. Saying you know better is not the same as explaining you know better.