In the IEEE latex package, I see that the paragraph spacing is set to zero (.cls file)
% Controls the spacing between paragraphs in lists. % IEEE does not increase spacing before or after paragraphs % so this is also zero. % With IEEEtran.cls, global changes to % this value DO affect lists (but not IED lists). \parsep \z@
However, in the output PDF file, I see some spacings.