To me, far left and center left politics are differing degrees of the same belief, whereas center right and far right politics are two different creatures that cannot be reconciled.
I think it depends on the type of far-left you're talking about. If you mean Libertarian Socialism/Anarcho-Communism or whatever you want to call it, then yes I think that's a different degree of the belief chain running from Left-Liberalism->Social Democracy->Democratic Socialism->etc. But if you mean authoritarian communism (Stalinism or Maoism for example), then no, I think that is a completely different belief system than the modern (at least developed world) "center-left".