It's definitely true in certain cases, induced demand is not some law of physics. Take a one lane road and a two lane road. It's pretty common for one lane roads to end up clogged up due to left turning traffic that's unable to clear intersections fast enough. On a two lane road, traffic that goes straight or right will have room two maneuver around the left turning traffic. And on top of that, planners for highways are really planning for throughput rather than commuting times. When you widen a freeway, speeds don't change or might even go down, but total throughput goes up accordingly and that's whats important when you have a mile of trucks backed up at your port.