Explore a critical examination of provable security in cryptography through this Eurocrypt 2012 conference talk by Alfred Menezes. Delve into the complexities of non-tight reductions, focusing on the classic Bellare-Rogaway proof for RSA-FDH in the random oracle model. Examine identity-based encryption schemes and investigate the importance of tightness in security proofs. Analyze MACs in multi-user settings, comparing single-user and multi-user scenarios. Evaluate Bellare's security theorem for NMAC and interpret its practical implications. Consider the PRF security model and its assumptions. Discuss the significance of non-uniform complexity models in cryptographic proofs. Reflect on the COPS (Cryptanalysis of Provable Security) approach and contemplate a radical proposal for the field. Gain valuable insights into the challenges and future directions of provable security in modern cryptography.