Anders,
what you are missing is that VFR flights are only seperated in airspace classes A through C (cf. ICAO Annex 10, Appendix 4). Apart from this, you will seldomly find IFR traffic at FL 40 in uncontrolled airspace. Firstly, FL 40 would only exist in a hypothetical country having a transition altitude which is low enough, and secondly such a low flight level would mostly be in uncontrolled airspace.
Edit: Sorry, the part after 'secondly' is rubbish. Forget it, please.
Last edited by hvogt; 17th Aug 2012 at 09:55.