After my reasonably succesful wood weathering experiments, I thought I might as well try the technique for real. Since the fishing boat Majestic was on the bench, and although I didn't want it to be dirty I felt the deck looked too pristine, it was the obvious candidate.
The alcohol and shoe polish mix was painted on and initially sat between the planks. Drying it with a hairdryer showed that the wood surface was being affected, but it appears the desks come with a thin varnish on them. That's good as it stops thew wood warping if you take a wave on board, but I wasn't sure it would be so helpful for my purposes.
After a couple more coats though I think the greying effect works well. In the sunshine the wood looks new but worn. A few more washes would have reduced it to a more faded huge. And I have another boat in the stash that needs to be a lot more careworn, so we;ll see how it pans out in the future.