Operator precedence is so deeply burned into my brain I would never think of adding parens for it or modify the spacing.
I will use parens, however, for << and a couple other cases. It would be a shame to use lack of spacing to imply precedence, and yet get it wrong. Oops!
I also like to line up things to make vertical formatting of similar expressions, something a formatting program doesn't do. Hence I don't use formatters.
Parens were not the main part - main part is having multiplication without spaces and addition with spaces.
I would say it is a neat detail but if no one cares or uses it - it is pretty much "feel good about yourself" use and not practical one.