Answer
The 4000-character limit is only enforced by the client UI, not by the actual database/deployment layer — you can edit the IAL's underlying file directly (outside the client) with the full, larger SQL statement (up to roughly 32,000 characters) and deploy it that way, bypassing the UI's input-length restriction. This is a workaround for the UI's own limitation rather than a real platform ceiling on IAL statement size.