I think the point is, you should be confident and competent using the brake levers on the drops. In-line brakes work great, and so-called 'suicide levers" work great too assuming they are quality and set-up correctly. But these "accessories" are not intended as a full-time substitute for the primary levers. Of course, if you go the fixie route you can always opt for flat bar levers and do away with the drop levers entirely - but that's a major variation from road bike riding, and requires new skills. So, even if you get in-line brakes, you should "learn to reach for the brakes quickly".