Robbie Griffiths is under no illusions about the task facing William Reid Stakes outsider It Is Written.

But the sprinter's affinity for the Moonee Valley circuit has convinced the trainer to roll the dice and give him a crack at Friday night's Group One sprint.

"I don't believe he's a genuine Group One horse and I think if some of those other horses are on their A-game, like Samaready, we're probably just going to run midfield," Griffiths said.

"But he does excel at Moonee Valley and if he's going to run out of his skin and run above his natural talent you'd think he'd do it at a track like that."

It Is Written has five wins and five placings from 13 Moonee Valley starts, including a Listed victory last Friday night and a Group Two placing in the Australia Stakes in January.

His success at the course is part of the reason Griffiths has nicknamed it "Money Valley".

"It's been good for us over the years," he said.

"We've been fortunate to have had a few horses that have really liked the circuit and because of that we keep coming back there."

Former stable stalwart Dandy Kid is the most notable Valley specialist winning there a record 15 times.

The Griffiths-trained Girl In Flight is untried at the track and her performance in Friday's Listed Alexandra Stakes will help determine whether she heads to Sydney or Adelaide for feature races.

Griffiths said the filly had trained on well since her second-up fourth to Solicit at Flemington but was unsure if the smaller Valley circuit would suit the backmarker's racing pattern.

"I expect her to run top four and the difference between fourth and first will be just how she gets around the tighter circuit," Griffiths said.