In "theory"... is it reasonable

What you should do is sneak over and take photos of Phillipa doing all sorts of unmetionables on the furniture and then post them to the neighbours.

I would.

Yes, I am fully aware of this, which is why Mr PKM was discouraged from initiating plan A, and plan B.

Of course they wouldn't worry - we're not really going to do anything to them.

We've just lost all privacy, as well as enjoyment of the woods, deer, foxes, birds, trees, where once there was established woodland and trees on 3 sides there is now a monstrous 'forehead' of tweeness... and a completely different 'view' from the back of our house. (it is the house on the right in the pic, the neighbour in question is on the left and they have 'looped' around our boundary)....

So, we're having a bit of fun at their expense, we'd never stoop to vandalism or trespass (although plan A was the purchase of a wrecked caravan and leaving it on their drive in the middle of the night, without wheels) we kinda figure if we have to now 'enjoy' their garden, that we should return the compliment. The doll is temporary, we can't leave it there when the kids are about....

Thanks to those who made suggestions on this... there was a serious point aside from the tying of inflatable sex dolls to trees...

Unfortunately the house is neither in a conservation area, nor do the trees have preservation orders on them - apart from the ones at the front of our drive which we need mutual agreement from the residents of the lane....

Bugger...

But rest assured that no dolls will be harmed this summer... instead, Phillipa (and friends) will enjoy co-incidentally timed, strategically positioned garden tea parties.

If they ever tell you they're bothered by it, claim that it's "art" and that you have been involved in it for many years- the only reason they can see it is because they've chopped down the trees...

PK they have still changed the use of the land though - have you followed up on this? I know a friend of mine did similar (joined with the neighbours to stop dev. of a bit of arable behind them) and they have been told in no uncertain terms that changing the use to garden will be met with some serious consequences.