I have been wearing sgians for a long time and while I get many comments on them (I own several interesting ones) I rarely have anyone specifically ask to see it. If they comment I usually just say thank you and leave it where it is. My personal opinion is that it should stay put unless you are actually using it. Which is highly unlikely with a dress sgian.

When it comes to my dress sgians, some have edges and some don't (even some very nice and expensive ones came without a sharpened blade). Since I don't plan to be doing real work when in formal attire I have never sharpened one that came without a proper blade. Sgians for daywear are another story and all of mine have proper sharpened blades. Personally I would leave it be.