One can 'baton' with a smaller sub 5" bladed knife, it's the technique and wood selected that gets the job done. Find yourself with a 3" bladed knife and have to cut wood, ok...Just find wood in the 6" and under diameter and baton on opposite sides of the log and sure enough your cuts will meet in the middle and split 'er!
My favorite belt knives are my 2 BRKTs, Mini Northstar is really an unsung hero in my book, a very versatile knife for it's size. Often underestimated, but it gets the job done many times to other's amazement. Next is a newer to me knife, the Colonial Patch, this is one sweet little knife that you have to use to appreciate IME. I rotate the 2 in my EDC and along with a OHT SAK, are my favorites so far. They all can handle most of the regular camp chores short of felling trees, and that's why you also carry a hatchet!