Unfortunately, Lizzie, if you work in a medium like broadcasting - where you're essentially a freelancer - such decisions, which affect your own future in the medium, are not easily made.

No-one lasts for ever - and rather than blame Mark Radcliffe for taking up a job which advances his career - if there was a "nasty little arrangement", then castigate Smooth Ops/BBC. Let's suppose that Mark Radcliffe had done, as you might see it, the "right thing" and refused the job. Would that have changed Smooth Ops' decision to release Mike Harding? I doubt it very much.

They wanted a change - they got a change. The manner of that change may be open to debate, as is obvious from this thread. But let's not be naive about the nature of the way that broadcasting operates and has always operated.