Either method alone leaves a lot to be desired and in the wrong hands can lead to failure. Instructional design concepts are extremely valuable so why throw them away because someone doesn't understand their value? Why not use them as a starting point with the understanding that evolution will need to occur to stay relevant? This will save more time than it requires. The evolutionary process for coding may work from the programmers perspective, but I have seen it produce un-usable products for education. Starting with basic instructional design concepts and then evolving is needed. Streamlining the design process and hiring more experienced designers is a better solution than doing without any design, but for some reason it is not common knowledge yet.