"It's difficult when there's two of you,'' Richards says. "We're competitive but Tim's been amazingly supportive. He's coped a lot better than I would have if the roles were reversed.''
Richards will ride 12-year-old New Zealand-bred bay gelding Flintstar at the Games. A wrist injury meant she opted not to ride him in Aachen, instead allowing Todd to take her place in the dressage and showjumping before pulling him out prior to the cross-country.
"[The wrist injury] was a silly little accident that occurred when I came off a young horse,'' Richards says. "It seemed an unnecessary risk to take part. I've been working with Mark and the horse since Christmas so I decided to play the sensible card.
"The idea was to let the horse sample a competition like Aachen which had the atmosphere of the big stadium. It'd be hard to find anywhere else in the world with up to 40,000 people flocking in to watch.
"I also don't think there would be many teams who'd have the same trust between team-mates to work so closely developing a horse.''
The team has had a further chance to put trust into action at last week 's four-day camp in Surrey. It enabled them to bond and practise the weakest area of their eventing programme.
"Our biggest concern is getting left behind in the dressage,'' Richards says, who did not compete in last year's test event at the Greenwich Park venue. "You're competing with the supreme movement and presence of the German and Dutch horses. The cross-country is where New Zealanders tend to be in their element as tough, determined riders.''