" Better control will enhance your ability to avoid negligently shooting yourself or another person. "
Better control will enhance you ability to shoot the person you want to, thus enhancing its lethality.
"However, being concealable does make the gun more deadly."
Glad you agree.
"Preventing someone from accidentally burning a hand doesn't make the rifle more or less deadly. The chance of burning your hand makes it less safe. "
If it allows you to use it in CQB in ways that you cant other rifles then it does.
"A suppressor (silencer) would reduce the sound of a gunshot to about the volume of a chainsaw a few feet away, far from an undetectable level. Suppressors are still ATF restricted and not generally available."
Still makes it easier to evade detection, and when it comes to all battle, seeing the other person or knowing where they are and not being seen or known where you are it is everything. That makes it more lethal.
So the XM-15 and the Ruger are exactly the same? There is no reason you would want the xm-15 over the ruger if you were trying to kill as many people as you could? You could carry both of them the same if you were in a hallway about to peek around a corner? You couldnt burn your hand if you put it on the barrel of the ruger unlike the xm15? The ruger is as easy to control as the xm-15? Please. That's like saying a Jeep Rubicon and a Jeep Sport with the same engine are the same thing overlooking all the things that make it a rubicon. I mean they are both 4x4 right? The front and rear locking diff's on the rubicon dont really make it better since the sport has 4x4 also? They have the same engine? See, they are the same.