The 36-year-old is one of the few players in Mark Warburton's squad to have experienced an Old Firm game previously.
The veteran forward has been leading the line on a regular basis since Martyn Waghorn last played for the Scottish Championship side, and O'Halloran - who is cup-tied for the Hampden Park showdown having already played for St Johnstone earlier in the competition - believes that it could be his presence that helps Mark Warburton's men in their quest to clinch a place in the final.
"Kenny is brilliant and since I have been here he has been different class for us, not just on the park but on the training pitch every day as well," he told the Evening Times.
"His experience, his quality and his intelligence is great to see. He has been great for us and I can't speak highly enough of him. He will be very influential against Celtic.
"He has still got a good few years left in him yet. He is a good player and a good person to have around the squad and the dressing room."
Miller has been hugely impressive this season for the Light Blues. Only Waghorn has bettered the 36-year-old's tally of 13 league goals, and he comes into the game against the Hoops having scored five in his last six games in all competitions, including the last goal in the Challenge Cup final victory over Peterhead.
And perhaps vitally, he is one of the only players in the Gers' squad to have played in a game between the two clubs previously, and has experienced it from both sides of the fence having spent just over a season at Parkhead.
That experience will help those younger members of the squad that are less aware of the pressure cauldron that they are about to step into, and will undoubtedly allow Miller to settle quicker and perhaps make the difference that O'Halloran is tipping him to make.