I don't use a power thicknesser to reeduce the back to the required thickness. Call me masochistic but I just like the direct contact with the wood that hand-planing brings. It's a very satisfying process and allows me to judge how the wood is responding to its dimensions acoustically. Tear-out is sometimes a problem for me with a standard blade though, so I've been trying out a new Kuntz toothed blade (from Workshop Heaven) in a Veritas no. 5 smoother. It takes a little while to set-up the plane with this blade - a slightly wider mouth is helpful, I find - and it leaves a very textured surface but it does eliminate tear-out almost completely. And the surface can be finished with a cabinet scraper really quite quickly. So I'm a convert to this innovation! Here's the back so far.