At the least, it implies that you ought to carefully consider whether you should. Optimized code often makes trade-offs in complexity, flexibility, etc, not to

At the least, it implies that you ought to carefully consider whether you should. Optimized code often makes trade-offs in complexity, flexibility, etc, not to mention the extra cost in development time. With those costs, there should be a compelling benefit that you get out of it. Otherwise, it's not worthwhile.