Friction isn't a part? But then why do I have to drill down to some arbitrary lower level? Why can't I stay above the biochemical level. It is to understand the more detailed workings isn't it. And friction is a part in the sense that it is the atomic parts and their interaction. I can't understand the failure of my mousetrap without understanding it at that lower level.
Details?
Why? It doesn't matter does it? We are discussing biological systems.
However:
How Can Evolution Cause Irreducibly Complex Systems?
Some things are clearly living, some are clearly not; some things are clearly plantes, some are clearly not.
Then I guess we have to go for some examples of things which clearly are and are not and some nearer the border to see if I can discern just what is and isn't IC.
As noted above it turns out the mousetrap isn't. Somehow Behe's examples keep failing when examined more closely.