An Achilles heel (n.) is a weakness you schedule the rest of your strength around.
The Achilles heel (n.) gets discussed by everyone in the room except the person standing on it.
An Achilles heel (n.) is a weakness you only get credited with once everything else about you works.
The Achilles heel (n.) is of man is generally his spine.
Akrasia (n.) is called 'weakness of will', a misleading metaphor — there is no will; 'weak will' is a multiplicity of impulses without a centre of gravity, 'strong will' their coordination under one.
A Blind spot (n.) is what you cannot see until someone else is already yelling.
A Blind spot (n.) is like a stain on the back of your own coat, obvious to the room and out of your reach.
A Blind spot (n.) is not a gap in what you see, it is a gap in what you check.
A Blind spot (n.) is the thing you would have noticed about yourself if you had been anyone else.
Delicacy (n.) is the parent of decency.
Delicacy (n.) is an attribute of heaven.
Delicacy (n.) is taste refined until almost nothing is left to taste
Delicacy (n.) is the difference between a compliment and a lawsuit