Believe me, I'd much prefer to pound the post in. I had use of a King Hitter series III post pounder for awhile. It needed some repair, and fabrication of some parts before it was useable. In exchange for that, and due to the person situation who owned it, I had use of it for awhile. So…..I'm well aware of the advantages of pounding the post in versus digging a hole. I hated it, when I finally had to give it up.
One of the 'parts' we did not fab up was a cap that slide on the mast to hold the post next to the mast. We made one for pipe, but not for wood post. Due to the lack of that, I found, it was really easy to get the post going in crooked. I learned you used small 'taps' and checked the post with a level, and repeated until it got a good start in the ground, then I could pound hard. If you didn't correct it in the very initial stage of pounding….on each stroke…you would not have a straight post. How do you go about keeping that post straight?
Pounding in pipe, not an issue at all, regardless of soil condition. Now I was pounding in 7-9 inch post, small telephone pole types…and even a couple of railroad ties. And the ground literally shook when I pounded those in. Wet soil or not, based upon this pounder use, I would of thought that would be tough to do the way you describe. But your experience is telling me …it works, so I need to give that a try. Guess I'm missing how much the wet soil changes it. I got black gumbo in some areas, so dunno...but I'll try none the less. I know with tpost right after a rain, once I literally pushed some in by hand. Let me know how you kept the post straight, or if you found it an issue. . BTW have a M7040, think it would be up to the task? Also I'm very envious of your ANBO. I could really put that to use.