Thes days on my stockman knives, I use the clip blade for most chores. I keep the other blades sharp and use the Sheepsfoot for making precise cuts and the spey for cutting things that should not be poked. I realize the last sentence sounds odd. An example. I helped my son buy a new suit. The coat pockets were sewn shut. I used the spey blade to gently cut the threads holding the pocket closed with no fear of damaging the fabric. I don't use the spey often these days, but it is there for when I need it.
A number of years ago I worked in a lab. One of the things we did was produce special sheets of rubberized material that were bonded to a stiff backing. I used to keep the spey blade of a stockman fairly dull so that I could use it to trim the rubber material so that it exactly matched the size of the backing. The blade would cut the rubber without cutting into the backing.
Tanto: never had one, never will.