Proposed BIP for OP_CAT

The email discusses an old limit that predates segwit and may even predate P2SH. The sender expresses a thought about replacing the stack interpreter data structure, but feels that it would be too invasive to justify the benefit. They mention that one of their favorite aspects of this BIP (Bitcoin Improvement Proposal) is the small difference. The email is signed by Andrew Poelstra, who is the Director of Research at Blockstream. The sender's email address is apoelstra@wpsoftware.net and their website is https://www.wpsoftware.net/andrew. The email ends with a quote: "The sun is always shining in space -Justin Lewis-Webster."