I have found that Max has a tendency to eat empty symbols in my patches. If I create a new object box and type in:
Max will replace the "" with a space, but the object will work as intended; it matches if I send it an empty symbol. However, if I save the patch, close it and then reopen it, the space is gone and the sel object behaves as if it had no arguments. I find similar behavior for route and message boxes.
Not having the empty symbols properly supported would be annoying, but what’s far worse is that the patch works one way, and then works differently the next time i reopen it.