Nice suggestion...but, no, the spindle is not diagonal. I inspected the BB and BB shell for damage and theres nothing wrong with it. It spins straight and smooth; the bottom bracket is undamaged, installed correctly, etc. The crank arms are simply not perfectly 180 degrees opposite from eachother. As noted above the crank arms and square tapir part of the spindle are in good shape, not rounded...all I can figure is that the spindle is twisted.