Self-Speculative Decoding Cuts AI Reward Training Time Without Quality Loss

Researchers have introduced a technique called self-speculative decoding to speed up the reward-based fine-tuning phase of AI model training, where models repeatedly generate answers to practice and improve. The method creates a compressed, lower-precision copy of the model at each training step to quickly draft text, while the full model only verifies those drafts rather than generating every word itself. Because the clone is rebuilt from the live model at every step, it stays in sync with the constantly changing training model and avoids accuracy drift. The system also intelligently disables speculation when hardware is already at full capacity, activating it only when spare resources are available. The final trained model is identical in quality to one trained without the technique, making the speedup effectively lossless — a notable claim in a field where efficiency gains are often overstated.