Alternative method of erecting non-structural wall – GreenBuildingAdvisor

I finished the structural wall of my workshop, and installed the first section of non-structural wall. This design has a 2×4 inner wall that is structural, an outer 2×3 wall for holding the siding and WRB, with the two walls held together by 2×10 top and bottom plates and OSB gussets. 

I was warned it would be time consuming to do it this way, and so far that has proven correct. However, it occurs to me now that there is a dead simple way of adding the outer wall that would be five times faster, and I can’t see why it wouldn’t work. Can I just delete the plates from the 2×3 wall, and instead make 2×3 I-beams that nail to the 2×10 top and bottom plates? 

I will confirm this with the engineer, but I’m hoping to keep working on this through the weekend and he probably won’t respond before Monday. If I have a pretty good inclination that this will be ok, I’ll take my chances and proceed.

I’ve attached the plans and a couple of pictures showing the fully assembled 2×3 wall and and an example of the I-beam I mentioned. I haven’t installed any gussets yet.