I'd be interested in how significant the actual performance hit is - I see no measurements. There are plenty of times you'd want to enable various debug featur

I'd be interested in how significant the actual performance hit is - I see no measurements. There are plenty of times you'd want to enable various debug features, even in production, even if it means leaving them always on. The only real question is if the tradeoffs are worth it - the performance hit, if any, and the security implications, if any, versus the productivity gains.