Craig,
I generally carry four also on my person. A Wave on my belt, Sebenza in rear pocket, Squirt on keychain, and Minichamp in my other pocket.
That doesn't count the Leatherman Juice in my bag that I take to work everyday, or the knives/multitools in my vehicles.
When I am cycling I usually have my keys with me (and therefore the Squirt) as well as an Alien multitool, which does have a knife blade on it, as well as many useful bike related tools.
So no, I don't think four is too many at all...
Greg