Thanks for the perspective, Jerry,
Topping the tree is an option, and when the crane operator was out to have a look, we decided to do that to help ensure it not getting hung up if falling it and to reduce the weight. I do like the idea of leaving it on to help possibly soften the crash, as has been suggested, and with a pull line and beefy puller, and seeing what it might brush up against, After some consideration, I don't think getting hung up to the point of having to recut the bottom is much of a concern. Besides the risk, there is the quality of the log that would be compromised. The biggest "yes sir" complication is that the priest wants the log in it's length entirely below the top, and my guess is that the weight is too much for a pick, even for the operator that is a fine one. He may have a different view. I will say that I have never seen a tree done in one shot of this size with the 25 ton. The priest might be convinced to change his mind.
I would follow your heed and not try to attach to the stump, there are other trees to anchor to. Some shock loading seems inevitable.
One good consequence about this job is that I have been reading up a lot on wire rope. Our big hardware extravaganza store pulled out a whole mess of old chokers and is offering them for 30% off, everything from fifteen millimeters to 25 mm, and three to five meters in length. All with spliced loop ends and a swaging ferrule as well. You usually don't see them with both. I might pick one up and have been checking out the strength options and learning about what I am looking at there with the chokers. 25mm is strong stuff, but quite heavy and stiff for sure when handling it. One thing that appears quite clear from pursuing the different manufacturer's websites and information, is that when it comes to shock loading, all bets are off regarding breaking strength. The breaking strengths they give are under specific ideal testing conditions, the same as rope I believe, a slow increasing in amount pull until there is a break. They don't seem to want to venture a guess as to what shock loading is going to do to breaking strength, basically predict undesirable consequences and just advise you not to do it. I also find a fair amount of divergence when it comes to wire rope breaking strength, depending on manufacturers, but using the same type materials and construction for a specific type rope. It gets a bit confusing in that regard. Like with arborist ropes, the recommended working load limits are well under the breaking strengths. I know that most guys doing removals seem to be more into ropes than cable, and I picked up a Masdam myself recently, but our endless cable pullers have been a mainstay when doing removals here, a superb tool in my opinion, so cable is something that has always interested me, but I hadn't looked into it much before, other than using it with some knowledge of capacities. Another thing I learned is that chain is pretty darn weak, until you get into the bigger sizes. It's all a pretty deep subject. I think we will be getting to that tree in about ten days.
A mistake still looms big, that's all.
Ten times the budget to remove that tree and I might break even. Slowly I've been collecting things, however, from people I know. The metal fabricator down the road loaned me an 18mm wire rope choker, and a pretty good length of 13 mm wire yesterday.
