http://www.youtube.com/watch?v=GO376G4tbGM&oref=http%3A%2F%2Fwww.youtube.com%2Fresults%3Fsearch_query%3Dhalo%2B4%2Btraielr%26oq%3Dhalo%2B4%2Btraielr%26gs_l%3Dyoutube.3..0i10l10.368.3721.0.4121.16.13.1.2.2.0.135.566.12j1.13.0...0.0...1ac.1.7t_TsdLCNwQ It's the "Scanned" trailer.
Also
Are you saying that the clones don't have the same lifespan as humans? Because if so I didn't know that and that makes sense. Otherwise I think the clones are clones and would have the same experiences and memory as those they are cloned from. Even if that weren't the case, they are cloned children, the original children don't have too much military knowledge either