Model Performance - GPT 4.5% is considered much smarter than previous versions, specifically 40 and 4.1% [1] - Despite its intelligence, GPT 4.5% is deemed not very useful due to being too slow and expensive [1] - Overparameterization caused GPT 4.5% to memorize data excessively during initial training, hindering generalization [2] Development Challenges - OpenAI encountered a bug within PyTorch during GPT 4.5%'s development, which they identified and fixed [2] - The bug fix on GitHub received positive reactions from approximately 20 OpenAI employees [3]