Representative “democracy” alienates the common man from the political process while maintaining a semblance of democracy. For this reason it is the ideal political form for capitalism, an economic system which alienates power from the masses and concentrates it in the hands of a few.
Class interests are the primary axis on which all political activity turns. Getting the working class to does not help them, it helps those in power.
Representation is necessary as a matter of scale, though. There are other issues with small r republicanism that are more specifically nefarious, like the legalization of bribery, the tilting of power towards land owners via the senate, etc.
With modern technology I wonder how necessary representative style governments really are. Electronic voting already exists and works quite well, and is probably the most secure form of voting as long as it can be audited. Of course, at some point administration has to come down to individuals, but as long as those individuals are held accountable in some way then it seems that the actual democratic step (i.e. voting on policy) need not be mediated through representatives as is oft repeated to justify the status quo.
You might have been referring to this with republicanism, but there are different types of representation, too. Parliamentary democracies are not obligated to obey the wishes of their subjects, whereas soviet (council) democracies are a form of direct democracy, where representatives are merely delegates and are obligated to obey/communicate the wishes of their subjects. In my comment above I had in mind the parliamentary type, since that is the kind in which there is a buffer between citizens and political institutions which is used by the bourgeoisie to suppress changes which would undermine capital.
