Come on GLP, his left hand touched his shoulder. Any 13 or 14 stone man running at speed touched like that wouldn't (or shouldn't) go down like that.
Richard West appears to keep getting lots of the top games as linesman. Wonder why he doesn't push to be a ref.
He used to do some stuff at Hull Indoor Sports Centre. I think he started his refereeing courses when he was at college - so 1991-93.
The only reason the defender put his hand on the other players shoulder was to try and slow him down. If that's against the rules it's a penalty. The falling to ground was a dive to con the ref. The hand on the shoulder doesn't (or shouldn't) cause you to fall over. There....sorted.