"Saying 'no offense' doesn't make offensive things okay, but 'with all due respect' somehow works"
"No offense, but..."
"With all due respect..."
It's the business casual outfit of insults. You're still insulting someone, but you're wearing a tie while doing it, so it's somehow acceptable in meetings.
Doesn't Work:
"No offense, but your idea is terrible."
Everyone is offended
Somehow Works:
"With all due respect, I believe there may be some challenges with the proposed approach that we should consider."
Translation: Your idea is terrible, but in Arial font
The secret is:
1. "With all due respect" = +10 politeness points
2. Use complicated words = +5 professionalism
3. Never say exactly what you mean = +15 diplomacy
4. Result: You can insult anyone professionally
"With all due respect" is corporate speak for "let me destroy your proposal while maintaining eye contact and drinking coffee." It's less "no offense" and more "yes offense, but make it professional."
The phrase "with all due respect" actually implies "I'm giving you the exact amount of respect this deserves," which, in context, is usually zero. But somehow wrapping an insult in formal language makes it acceptable.
It's like putting poison in a fancy bottle—it's still poison, but at least it looks classy on the shelf.