Evaluated with ±2 standard deviation requests on held-out LibriTTS-R speakers, SteerTTS achieves Spearman correlation coefficients between 0.87 and 0.97 for loudness, median pitch, H1–H2 and spectral tilt; however, ρ is only 0.46–0.79 for pauses, voicing ratio and CPPS, and CPPS leaks into pitch and level.