Earlier quoted context omitted.
The memo does nothing to establish whether Samsung is infringing patents. But this is just the sort of thing that sways juries. And trials are about juries. So yes, this is how the system works. Both sides putting in enormous effort over admissibility of minor documents, outcomes swayed by minor missteps.
I think the iPhone sketch with a Sony label was far more damning to Apple than this memo is to Samsung. ( http://www.phonearena.com/news/Samsung-claims-Apples-iPhone-... )
You're right that it's a great parallel and perhaps even more so.