In short: add me to the "yes" camp. The only reason mine's not very sharp is 'cause it's a cheapie knife and the blade simply started going to bits when I tried to sharpen it (I figure if I ever need to use it, I could still stab someone).

(My mum, who is often my Games-going companion as she likes to watch my dance competitions, keeps asking me if it is "legal" for me to wear my sgian dubh.)