A neighbor of mine has an outdoor wood boiler that he uses to heat his home and shop. He doesn't split his wood either, but it is probably more dry than the average split wood.
What he does is cut "cookies" from the logs. He has a high powered chainsaw (might be a 660) and cuts about a 4" slice off the log. Then we he stacks it, he lies it flat and leaves space side by side between each "cookie", and then stacks more "cookies" over the gap created by the space, and continues like that.
It takes up a lot of space but you can tell the wood is very well seasoned by the cracks and checks opened up in the cookies as it shrinks while drying.
If I had a large wood boiler I'd try this method.