The following was a comment of mine on an answer on Stack Overflow:
This answer is misleading and incomplete at best. Plain wrong at worst.
My intent was to express that an indulgent interpretation will render it misleading and incomplete. A less forgiving one can go as far as saying it is just wrong.
I don't feel good about at worst. Is it a correct way to express this? I suspect it is, but even if it is I have the feeling it doesn't sound natural to an English speaking native.
Best Answer
Perfectly comprehensible but seems rather brusque to me (BrEng).
"case a at best, case b at worst" is normal usage. Where case a is bad and case b is even worse, it's a pretty dismissive thing to say.
It gives you you opportunity to criticise and then double-up on that criticism. Since your case a consists of two things ('incomplete' as well as 'misleading'), you've been able to go for triple-criticism. Harsh.
Star Trek: Deep Space Nine: The Siege, Peter David