To be fair, I think a lot my prejudice against overriding operators is summed up by Bruce Eckel (who explains why it is arguably misguided in the case of Java):
"[Java designers] thought operator overloading was too hard for programmers to use properly. Which is basically true in C++, because C++ has both stack allocation and heap allocation and you must overload your operators to handle all situations and not cause memory leaks. Difficult indeed. Java, however, has a single storage allocation mechanism and a garbage collector, which makes operator overloading trivial -- as was shown in C# (but had already been shown in Python, which predated Java). But for many years, the partly line from the Java team was "Operator overloading is too complicated."
> it is not more reliable because you are assuming what "+" and "" do.
You also assume what "add" and "multiply" do.