Oliver, it is entirely possible, when reciting a mantra to have other thoughts. Think about monks reciting decades of the Rosary or signing Gregorian plain chant and contemplating or otherwise praying while doing so. Saying "pedal, pedal...." does not preclude other thoughts and internal conversations and may, indeed, prompt deeper ones.
Oliver, it is entirely possible, when reciting a mantra to have other thoughts. Think about monks reciting decades of the Rosary or signing Gregorian plain chant and contemplating or otherwise praying while doing so. Saying "pedal, pedal...." does not preclude other thoughts and internal conversations and may, indeed, prompt deeper ones.