All depends on the wood and how it is handled. This tree native to Tasmania can be submerged in water for a hundred years and will still burn and will not rot. http://en.wikipedia.org/wiki/Lagarostrobos
I seem to be opening up a lot of old threads again but for what its worth I picked through CL and asked about some free wood. 8 year old alder. Some in a shed some not. Some were out on the ground to keep holes in the fence for a dog. The shed had fantastic wood. Split in half but dry as it comes. I couldnt read the article the OP posted. Bad link. But relative humidity probably has a lot to do with wood keeping well too. When it goes back up in the rain season, its no use to fight that back. But any wood in a covered open shed would go well for awhile. Old Spark does mak a point About bound water and free water but then theres standing water which does our wood no good, makes it all a breeding kennel for any microbes that encourages dissolution. Age doesn't seem to factor but as long as it was split and put in the right place, wood can't really get too dry. Just too many variables depending on where you live. One person's stack can become mush while another could be 10-20 to 100years old if allowed. Haha now seems like we're getting into wood like whiskey is aged. Mmm smoky and smooth.