diggy_dude
Now 169% diggier!
I'm not saying the monitors should be lifeless. They should simply not flatter the mix, i.e., make it sound better than it really is. A good mix should sound good, and a bad mix should sound bad. You should be able to hear what's on the tape. A good mix isn't going to mean diddly if it's played back on one of those trendy new systems that doesn't strive for musicality in any case. But it's a safe bet it will sound awesome on a well-designed hi-fi system.