Harry's accent gets thicker and thicker as he's succumbing to the Truth Serum, and the way he constructs his sentences gradually begins to sound more like German than English.
Remember Dana in the beginning of the movie managing to steal Harry's partner's money from his coat without them knowing? It comes in handy when she steals the key to a nuclear warhead while being hostage to a room full of terrorists without being noticed.
Considering this movie's Reality Subtext, you can easily read the plot as a Take That! from Cameron in regards to his marital troubles: "You want excitement in your life, honey? Ha! Well, how's this for excitement? You think I'm married to the job? Well, at least I'm not using my job to be a creepy stalker!"
Harry and Helen get captured by the terrorists because Harry grabbed the Idiot Ball. Of course, if Harry hadn't been captured, he never would have found the terrorists and the nukes in time. Also, the whole experience helped reinvigorate his marriage and improve his relationship with his daughter.
Gib's Brutal Honesty regarding Helen's affair may seem insensitive—"What'd you expect, Harry? Helen's a flesh and blood woman and you're never there"— until you recall that Gib is the veteran of several failed marriages himself, which were very likely due to him never being around.
