I know its a sin to resurrect dead threads, but just wondering, 10 years later, how the asphalt or rubber coatings are working? I know the ACQ pressure treating isn't as good as the CCA-- had to do some repairs on the 12 year old deck at my mom's while we were in the US this winter-- posts I had put in the ground in concrete. Likewise, some 4x4 fence posts broke off at the base when a limb I was cutting off a tree hit the fence, they weren't older than 15 years. Coming back to Slovakia, some of the smaller black locust posts I used on our pasture fence have rotted in five years. Apparently, young wood on black locusts isn't resistant.
There is a product from England called a "Post Saver" which heat shrinks around the bottom part of the posts, but, well, its in England, everything shipping wise is screwed up by COVID-19, and I can get asphalt water proofing compound or rubber-asphalt underbody paint easily. Wondering if its worth the added cost and time to coat the bottoms of the new posts I'll put in (which will be either black locust, or some small oaks I've had to cut down).