I concur with what you're saying, IC - the role of Government is primarily to make policy and legislate. Regarding oversight and governance, independent agencies such as ICASA are the ideal mechanisms to ensure compliancy, provided they have the means and the wherewithal, as stated previously using other terms. Unfortunately, the direct organs of state (like the DoC and any other Department you may think of) do not consider such agencies as being of any consequence, and in fact see them as being subordinate to their own activities and status in the bigger scheme of things. When it comes to the DoC, I place the blame for much of this scenario squarely on the shoulders of the previous DG - technically a very solid resource, but a power-broker par excellence, as recent events have proved.
There are in fact oversight committees that sit in Parliament, and to which both ICASA and Telkrap have to report. There are also what are called 'clusters' in Government - these are inter-departmental forums, where matters of common concern between departments are discussed. I'm not sure who sits on the Communications cluster these days, but I think besides the DoC, the other departments are the GCIS, the Office of the Presidency, DoPW and DTI - I may be wrong, though.
Anyways, bottom line is that somebody has to 'crack the whip' - I recall posting some time ago last year that the way to fix things, is to fire the asses of the executive and the top decision-makers at Telkrap: and this, well before Sizwe's exorbitant salary and the obscene profits made by Telkrap came to light! Thankfully, the liberalisation directives of Dr Ivy hold out much promise of effective change, albeit not soon enough in the opinion of most - there is some light at the end of the tunnel, however!