"We'll see how it all plays out," said Leach, adding he is "pretty sure" Halliday will start against the Beavers.
"I think they're similar and both do some good things. Connor Halliday has given us a spark, so we've kind of stuck with him."
Leach, who did not play college football, said he reminds Halliday to make easy throws that even his coach could complete.
"He's trying to make too much happen on each play," Leach said.
He said the quarterbacks and wide receivers still need work to be synchronized in the Air Raid scheme.
"Improving, but we're not there," Leach said. "It's not as tight or automatic as it needs to be."
He said he likes to rotate eight wide receivers during the game to keep everyone fresh. One player who emerged against Oregon was senior Gino Simone, who had 65 yards on five receptions. Leach said Simone was inconsistent during spring practices and fall camp, but is playing well now.
"He was in the right place because he outworked and outhustled some people," Leach said.
Leach believes the Cougars (2-3 overall, 0-2 Pac-12) are improving each week, but will need to accelerate that process against the Beavers. Behind sophomore quarterback Sean Mannion, OSU is averaging 487.33 yards of total offense, which ranked 28th among Football Bowl Subdivision teams. Leach said the Beavers (3-0, 2-0) are not quite as difficult to prepare for as the Ducks because their offense is "more traditional."
"There's nothing easy about them," he said. "They're a good, solid football team."
LEACH SAID REVIEWING opponents' games now is easier than ever because it all is delivered digitally. He even has access to tape from teams such as Arizona and USC that WSU does not play this season. Leach said he will review those in the offseason when his time is not as limited.
He said that is much different than earlier in his career when teams were shooting and editing 16-millimeter film. He said some teams would not deliver film on time for a variety of reasons, and the ones that did might feature airplanes or "girls in the stands."
"You had some kid go up there and shoot and you didn't know what was going to come out," Leach said.
Because of the access his players have to game tape, he said he hopes they review it regularly. But Leach said NCAA rules prohibit him from placing mandates on how much time his players must spend watching opponents' games.
"There were plenty of people who were disappointed that the game was over, which I thought was a positive change," he said. "No one is satisfied with just a good showing."
"I really think they ought to grant it," Leach said. "If they don't, they might as well get rid of the rule."
He said he still regularly talks with Holgorsen, who was a Leach assistant from 2000-07, and the two share ideas.