Using "that doesn't work for me" as a euphemism for "no" sounds crazy to me.
I have also personally met people who,
- when I tell them "You're sort of right, but I have to disagree", hear "I agree with you".
- when I tell them "No, that's wrong", hear "I'm challenging your ego to prove that you're right!"
It takes a lot lot lot of nuance to discover how to communicate effectively.