If he was carefull, why would he leave any evidence ?
It's too big an if, especially if you have a Mensan's grasp of probability. Sure, it's possible to do it without leaving any evidence (physical traces or witnesses). It's just too damned risky. See Lanza's post number 421 for a nice analysis of all the things that could have gone wrong. The prosecution's case would be a lot more convincing if they were to present an account of the abduction.
BINGO!!! If he was SOOOOO CAREFUL - Why would he leave any evidence of her in his MH or on his jacket? I mean, after all - he doesn't shed hair now does he???