Radradra bagged the first four-try haul of his 70-game NRL career on Sunday night in the Eels' 34-16 flogging of St George Illawarra in Wollongong - marking the fifth hat-trick of his career.
He scored his first three tries on the left wing, completing relatively simple moves down the Parramatta edge and receiving the final ball from either Michael Jennings or Corey Norman.
However, his fourth and final try came on the right edge, courtesy of a slick inside ball from full-back Bevan French - surprising the Dragons defence.
But Radradra said the tactic had been one he and Arthur had developed over the pre-season.
"He let us do whatever we want to do," Radradra said of Arthur. "He never tells me to just stay on the wing. Sometimes if it stays quiet I come find the ball.
"It's pretty difficult to defend as well. The confusion is tough."
Radradra was quiet in the Eels' opening-round win over Manly last weekend, but was far more involved against the Dragons on Sunday night.
The 75th-minute move with French was not the only time Radradra drifted to his right, as he also set up on the opposite edge from a number of scrums and shifted in-field in the middle of sets.
Arthur said it was a tactic he would continue to employ.
"Semi has a licence to go and get his hands on the football," Arthur said.
"He's one of our strikes. We're not going to pigeon-hole him into one side of the field.
"It's very hard to plan defensively against him when he's doing things like that."
Radradra future still clouded
Radradra's future at the Eels is still unclear.
He has a domestic violence court case hanging over his head, with the next hearing due for May 2.
He has also signed to join French rugby club Toulon next season, however he could be forced out of the NRL well before that if he is found guilty on two counts of assault against his former partner.
But Arthur said Radradra was in a clear headspace at the moment.
"He's got a bit of clarity at the moment," Arthur said. "He likes being around his team-mates. His team-mates have been fantastic for him.
"We like to see a happy (Radradra)."