Hi Brian, I just replied to your post on the CLC board but I'll put the link here as well. Malcolm Schweizer used thin shavings glued over nail holes to hide them - the grain blended in really well. I think you might be able to use something like his technique to make use of all the left over ply scraps - take thin veneer shavings off them and hide all the stitch holes.

It would probably be time comsuming to do all those holes but maybe worth the effort - and while you're at it, cover those nails if you have them on the deck

here's a link to Malcolm's post