The sad thing about all those observations is, all these things surely happen anyway, and lots of people end up in jail anyway, because they don't have good representation to point out how they've been railroaded and they've got a plea bargain dangling in front of them.
People at least know "Nobody read me my rights", "I want to plead the Fifth", and "I want my lawyer" from seeing it on TV. If your arrestee-- or your jury pool-- has a higher level of awareness of common legal gotchas, they'd be able to demand a better deal. "I know you screwed up, the plea deal isn't good enough."