What is preferred lacing for PowerTap wheel build? I've done quite a few wheel rebuilds to make them stronger, but haven't built up a wheel around a PowerTap (SL+) yet. This will be for a training set for a fit triathlete. Raw weight is not an issue, but he's probably putting a few watts done for hours at a time.

My inclination would be to do my "standard" rear wheel build, drive side X3 and non drive side Radial, but wonder if there are pros/cons to other lacings when power is involved.
According to the FAQ on their website:


  Note: PowerTap hubs must be laced with a minimum 2 cross pattern to avoid damage to the hub and maintain the warranty."


That suggests that making the non-drive side radial could lead to warranty issues. Radial lacing does stress the flange more than tangential lacing so many hub manufacturers do not allow it. To work on a driven wheel it also needs a certain amount of torsional flexibility in the hub which large-flange solid hubs don't have (Rohloff, PowerTap for example).

I would go with a ye olde traditional 3x lacing, and lean more towards 2x and bladed spokes than other options if the rider wants to spend more money.