no, it's not. well, you may argue that death comes one second after someone is hit in the head. But the physics of the bullet hits the head should apply instantly. But in KZ2 beta now, you put a bullet into someone's head, he just stand there like nothing happened except for the blood splash. Then half of a second later, all of a sudden he starts a dramatic death animation like throwing arms into the sky and turning 1080 degrees before falling down to the ground. The whole thing just feels so out of place.
also, i don't see any other reasons that could cause the unusual amount of double deaths unless the game handles the gunfires in an extremely unrealistic way. I don't want to sound like a nerd but let's talk about common sense. The normal time interval between two bullets are fired from a assault rifle is about 0.085 sec (700 bullets per minute). At close range, say 10 meters (about 30 feet), it only takes the bullet 0.011 sec (900 m/s) to fly and hit the target. So most likely, there is only one bullet in the air between you and your opponent at any time. of course if you and your opponent both pulled the trigger within that 0.011 sec, you could kill each other at the same time. but the possibility of that happening is very very low.
anyways, whatever the reason is, i think the "death delay" is having a negative impact on the gameplay, or at least the "feel" of the gameplay. I think they should fix it.