I am one of the "no sharpener carried" camp. I have a variety of pocket type sharpeners but I find that on most all the trips I do or have done, I never need a sharpener. When I was in the military I carried a red (fine) DMT pocket sharpener in my kit. I carried it because if I was ever deployed, I could be in the field for an extended period of time.

In civilian use, I never carry one in the field. I have been on a lot of trips and never needed a sharpener and prefer to save the weight. I went on a 7 day Bushcraft course a few years ago and used my knives all day long and part way into the night. I took a Mora and a SAK Farmer. Both were razor sharp to start and not very much duller after 7 days making things and making fuzz sticks, batoning firewood, making spoons, bowls and traps. Good steel and good knife technique should be able to hold up for quite awhile without sharpening.