Be careful with mesh, it can dehydrate you and not cool you off. You're often better off sweating a little in a vented jacket (which cools you and minimizes water loss) than in mesh, which exposes you to a lot of hot air without cooling you. IMHO, the mesh temperature window is a narrow one.
Read The Patriot Post -- It's Right. It's Free.
Sometimes the light to see your way forward is provided by the bridge burning behind you.