The problem with using "simple" is that it's ambiguous. Are you talking about the opposite of sophisticated? the opposite of difficult? the opposite of complex?

The problem with using "simple" is that it's ambiguous. Are you talking about the opposite of sophisticated? the opposite of difficult? the opposite of complex? It has virtually no meaning without context. So if you're tempted to write simple, remove it and say exactly what you mean. Often times, documentation writers say "simply do X" when they mean "as a prerequisite, this document assumes the reader has an understanding of Y such that they can accomplish X without any further instructions". There's nothing wrong with having prerequisites; you have to assume the reader has some knowledge upon which to build. Make that explicit rather than hidden behind a "simply".