As I said in one of my first posts on this subject there will always be aircraft that CAN'T fit mode S for technical reasons. these aircraft are the ones that only fly in good VFR and so I don't see a problem with the exemption of these aircraft, this is what I shall say to the CAA.
I don't think that the this is an unreasonable position to hold but rather than jumping up and down and stamping my feet in rage about mode S I try to see the advantages of the system and use the best reasoning to get the most out of the CAA/Eurocontrol in fact ADS-B (that is in use in the USA and Sweden) is in a lot of ways a better system than TCAS and yet costs a fraction of the price.