Its not that there's no definition for the notation, but if you fall back to commonly held definitions, there is divergence in common definitions without the parenthesis. Plenty of calculators, especially old ones, don't respect PEMDAS, so the so by adding brackets your expression is going to fit the intended operations in more commonly used systems than had you left the brackets out.

I also do think its a bit more readable as your eyes are initially drawn to the first operation, you can start evaluating expressions without even parsing the rest of the equation, or you can just block out that entire chunk when you start looking at how many terms are in the equation. That's subjective though, so to each their own.