Oft-used

The "invisible hand" is an oft-used metaphor for the free market.

The late Professor Pat White was an outspoken critic. In his 1986 book Forgotten Railways, he dismissed as smoke and mirrors the oft-used argument that 33% of rail routes carried only 1% of the traffic, as it ignores the fact that a third of the national road network also only carried 2% of cars and lorries. But unlike rail, road got away with it because no mention was made of how much it cost the taxpayer to keep them usable.