I have to agree with Fuji here.
Mandatory (mode C) transponder carriage for all traffic in IMC would definitely be a step forwards as far as maintaining separation is concerned.
It would be entirely fair for people to fly into cloud with no transponder if their only risk was collision with another non-transponding aircraft.
More than a little selfish to wipe out somebody who had invested in additional safety equipment I think.
For those of us who believe that while travelling in objects closing at several hundred miles per hour in poor viz it is good to maintain separation then there is TCAS.
Having flown with TCAS for a few years now I am convinced it has improved flight safety for me.
The one thing that is very annoying is when traffic is transponding mode A with no altitude and you get a spurious traffic alert (as I did yesterday over Filton in IMC) which looks a bit like this
yellow dot. Believe me, there is nothing that makes you look outside the cockpit (and into the murk) more than hearing "traffic...traffic".
Low airway routings are simply not practical in the UK on any of the routes I regularly fly.
Coverage of IFR traffic OCAS is poor - I have also been dumped and told to "freecall XXXX" - no problem if VFR, but in proper IMC it is unwelcome extra workload.
SB