DRP,
We have done some testing on all wood frames mounted to wood construction, but the infill has either been metal inlay or cable infill.
Frame work to accept cable infill is the best comparison to just testing a post, it has been over a year since I read through the VT study, but the study from what I remember reading never really tested complete deck and guard assemblies, just the post connection, thus not allowing for other factors.
I would have loved to have seen them do complete common built deck designs and not just the post free standing.
As for 50' straight runs of wood guard being built,that is very uncommon in my region of the country from what I have seen. But if built under the IRC, would really not change much since the IRC is limited to just the 200 lb point load and not the 50lb P/LFT. If built under the IBC, there would be a lot of bracing up or connections like the study shows as a good construction method.
We do work on a fair amount of wood deck structures and our mountings are not much different with the forces applied, however our structured metal product does have a large advantage over all wood construction for a guard with spreading the forces applied.
Tom