Hi doug, thanks for the comments from a fellow owner. And those are exactly the kind of trails I love riding! Current tyre on the back is a 2.35 High Roller, and previously was a 2.1 Nevegal.
1. The bushes have gone on the shock, and have been like that for a while, and there's also wear on the shock shaft, so this is maybe the answer. Certainly the ride isn't as 'plush' as full-sussers that friends own, comparing back-to-back.
2. I'll have a wee look tonight, but externally there's nothing I have seen. These wheels certainly get a lot less abuse than the 717's on the hardtail, which I rarely pinch flat on.
3. Nah, tyres stay inflated.
I'm a bit of a brake dragger too – tend to sit on the brakes a lot, but will see what comes of giving the shock a service.