What would happen if Pat just breezily said - in response to Knob's ludicrous fending-off tactics, 'oh dear, poor Helen, but I'll just nip over there anyway to say hello, I'm sure she wouldn't mind'? And then go out to the car and drive over there.
He couldn't exactly chase after her and bar the way, or react explosively - that would show his true nature. But she doesn't do that - she just gives in, instantly. I simply don't buy the way everyone around H is submissively kowtowing to Knob....It's as if he hypnotises every single person he encounters (except Kirsty, who's not remotely susceptible, thank god).