Thanks, Terry and John.
I wasn't aware of the PS technique (although I've also whiled away many hours of my life on youtube, hours i'll never get back), but it's fairly easy to get a very similar effect in LR using the adjustment brush.
I confess I rather liked the leaves. The crop is an interesting idea but I miss the V shape at the top of the fall. I wonder if a less severe crop might work.
Interesting comments, as ever.
Jeremy