The Rhinos made it three wins from four matches on Friday night as they thrashed Hull at Headingley Stadium.
While admitting that his players were guilty of one or two "silly decisions" during the match, McDermott was pleased with their overall performance.
"I thought we were very good, the best we've been for a while, but we made a couple of silly decisions with the ball and a couple of soft errors. That doesn't detract from the fact that we were very good," he told Sky Sports News.
Leeds return to action this Thursday when they entertain Castleford Tigers in the Super League.