Regarding roads, it's not true that building roads can't alleviate traffic congestion---although there are special cases where building roads makes travel times. It depends on the network.

In general though we should expect building roads to reduce travel time. The fact that driving increases following road-building is evidence of this: why would driving increase if travel times between all origins and destinations stayed the same? Validated models of travel demand all depend on travel time, not the existence of roadspace. Just because driving increases upon building new roads does not mean it does so to the extent that travel times are unchanged.

For the record, I do not support building many more roads. They have become very expensive to build and maintain, the maintenance backlog in some places is severe, and in a thick network like many US cities have they do little good. In some cases the pollution they create is severe and disproportionately impacts poor people. But I still feel compelled to nitpick this common misunderstanding about induced demand.