racook,
the ballusters are infill only. If you do that calculations on that they do not have the capacity to cantilever and resist the code mandated loads on the rail (200 lb point load at any point and any direction or 50plf which ever is greater) this is true even if you gang a whole bunch...
glass,
that kind of stinks. After quite a bit of spinning my wheels I talked to my client (a custom fabricator) and found they typically have steel insterts in the wood rail due to this issue.....
