Good luck with your problem. I tried to find out about a product that was a wood cap made of Brazilian Curupay here about 2 months ago. Not one responder. The product needs to be maintained by staining regularly but looks wonderful to me. Don't know if it holds up or has any problems. It was featured on an episode of This Old House a while back and I googled till I found it. It was at ecoarbordesigns.com. This is not and endorsement because I have not yet purchased any. Wish I could find a site where someone has.

My problem with "deck caping" is your installing a new product over something that generally needs to be replaced or at the very least some heavy maintenance. And in my opinion it is really a bandaid and bandaids are generally meant to be a temporary fix or solution. Just my opinion but........

Sounds like a recipe for water trapping and accelerated decay.

Like all those 'maintenance free' clad windows.