True, the Romer model relies on increasing returns to ideas and labor.

It is an endogenous growth theory that internal processes can help an economy achieve tremendous growth. It specifically focuses on enhancing the country's human capital, leading to economic growth that stems from technological development and efficient and effective production. Human capital provides labor (a factor of production) which is paid in terms of wages. Therefore, we can conclude that it indeed relies on the premise of increasing returns to ideas and labor.