What do you mean 'as if'?

I once worked for a company which had a harrassed personnel manager who once said, "Why are all good programmers raging paranoids?"

I tried to explain to him that only people who expected everything to go wrong really understood what was going on.

Not to mention the fact that, for many, this paranoia has been learned through experience.

Programmer 1: 'There's a nice quote here - "Always code as if the person who will maintain your code is a violent psychopath who knows where you live"'.

Programmer 2: (Looks over at maintainer) 'What do you "as if"?'