Raise in production rather than silently continue

Counter-intuitive lesson from Joel Drapper: leave runtime type checking on in production. A raised exception with a clear message (what it got, what was expected) is better than quietly deleting 4,000–10,000 support tickets because nil was interpolated into a query. At Clear Scope, enabling Literal in production actually *reduced* the observed production error rate, because errors surfaced during development and tests.