That's why a log splitter is so nice. Split it where you want it. Now there's no guarantee that it will, with branches and such, but typically they will split right where you set the wedge.
I like rectangular pieces, I call them slabs. Last year I started a new, for me anyway, fire technique, I call it the canyon fire. Stack up four or five rectangular splits on each side of the firebox, slightly leaning in, fill the inner space with half kindling and a couple bigger kindling splits. Seems to get going fast and smokeless, and the splits will fall in on themselves.
I don't have a stove but that's exactly how I do it - mix it up both size and shape. I make a game out of it while swinging the maul - how to get the most variety as quickly, accurately, and safely as possible all the while reading the grain and learning about the round in front of me. I'm sure all of you are like me - when you grab a split sometimes you go "Oh yeah, I remember splitting this piece! That's a nice piece right there!!!"
I make mine at random depending on round diameter. Usually its halved then "pizza slice" split. If those are too big then half those. I would say my splits average out to the size of a 4x4 piece of lumber. Whatever works best for your situation.
I will try to make some rectangluar splits for cribbing and look for rounds for "half rounds," but really I just read the round and let the maul do its thing. I have some really large splits in my stacks for overnight burns, to much smaller for the wife and boys to more easily handle. Im consistent at being inconsistent with my splits.
