Of course, there needs to be a constant struggle not to over-complicate, but it should be done with the understanding that over-simplification is just as problematic.

I would like to differentiate simplification, aka "dumbing things down", from purification, which is finding the right frame of reference to enable a more compact representation of the necessary complexity. Purification is always highly desirable (unless it's just a facade used to make oversimplification more appealing).

The problem with purification is that you usually don't have the time to ruminate on your problem space for months.