They are attempting to push on and reach what would be their sixth final since last winning the competition in 1999.
Of course, although Leeds have won six Super League titles in that time, they have also lost each of those Cup finals.
There is, though, no reference to ‘hoodoos’ in the Headingley ranks or the fact Warrington have beaten them in two of those showpieces – 2010 and 2012.
“We won’t speak about that,” said McDermott. “We’re not avoiding it but it’s a new competition.
“We know they’re good in this comp’ but I don’t think it gives them any edge over us what’s happened in the last few years.
“And we don’t need any motivation.”
Warrington have lost two of their last three games after a 10-match winning run came to a shuddering halt but they did win in Perpignan last Friday while under-strength Leeds succumbed to relegated Bradford Bulls.
“It’s interesting they started off a bit slow this season then hit a massive vein of form and just recently had a couple of scratchy wins,” said McDermott.
“But it doesn’t matter does it? You can look back in the history books and see some teams have taken fantastic form into Challenge Cup games and then been beaten or, on the flip side, been really poor and gone on and won.
“We say the same thing about this competition every year but it’s true; it brings the best out in some teams and nervousness in others and no-one knows why.
“What Warrington did last Friday won’t affect how they’ve prepared for this and likewise us.
“We’ll be hugely disappointed if we lose but we’ve prepared well and realise the sort of performance we have to deliver to get back to Wembley.”
Leeds are boosted by the return of captain Kevin Sinfield after a two-game ban plus other key players such as Jamie Peacock, Ryan Hall, Kallum Watkins and Joel Moon.
“It’s good to have him (Sinfield) back,” said McDermott.
“He’s a big part of us and a big part of what we do. It goes without saying.
“I wouldn’t say anything as dramatic as we’ve missed him over these past two weeks but we certainly welcome him back.”