No. Sidious is described by Gillard as a master of all weapons and fighting styles, an accolade apparent in his training of Maul in juyo, which requires a mastery of the other forms. He may not be as technically skilled specifically in makashi as Dooku is, but his overwhelming strength in the Force still makes him too fast for his apprentice (see: pre-vaapad Windu and B-team getting sliced and diced).
IMHO the gap between Sidious and Dooku in saber combat is pretty enormous, as in close to blitz level. You have Luke/Sidious/Yoda, a big gap, and then Dooku/normal Anakin/base Windu leading the edge of the bell curve. I get this from Stover's depiction of Windu vs. Sidious before the former sunk into vaapad fully. Maybe Caedus rests somewhere in the middle, and possibly Krayt.