OK; thanks, SD.   

My reason for asking was because, not so long ago on (say) Wikipedia, you could find as many different definitions of "social democracy" as there were social democrats.  Tough for the rest of us to have much confidence in an economic system that no one could clearly define.

To be sure, more recent entries on Wikipedia are endeavoring to be a little less fuzzy.

You seem to mean a system of judicious checks and balances on a market economy.  All well and good; a pluralistic society such as ours needs checks and balances in order to function.  That's why we invented government in the first place - so you and I could keep an eye on each other.  ;-)