What you want is a flexible blade with a granton edge or "Kullenschliff". What this is , as Gasbury describes, are hollow dimples. As you draw the knife through mosit, sticky items-like smoked salmon, gravad lox, ham, cheese, etc. the air trapped between the dimples is squeezed out, forming a slight airpocket around the cut, making slicing a little easier.
This is not a gimmick, nor is it anything new, smoked salmon knives have been around for at lest 80 yrs that I know of, with this design, and in my day I've sliced many a side of salmon with this kind of knife. However this kind of a design on a rigid Chef's knife or Sanktou is moot at best.