The wood framed wall you're building might not be structural*, but that tension rod sure is! I would be very concerned about "capturing" it inside the wooden wall, especially in an earthquake area. What if during an earthquake, the steel structure moves one way, while the wooden structure (with a different resonant frequency) moves the other? The tension rod might get ripped off the steel framing, causing the frame to fail.
Also, how would you nail the studs while wrapped around the rod? You could toenail, but the wall will turn out a lot better if you assemble it flat on the ground and tip it up.
Is this on the non load bearing wall? If so, 2x2 framing might be enough to hold up wallboard. If you need to reclaim every possible square inch, I might suggest building the wall conventionally with 2x4's, and then notching the back sides to clear the rod. At the notch, they'd be down to 2x2's, but as the notches are staggered, the wall would have most of the rigidity of a 2x4 wall.
* From your other post, you're putting a floor on top, so your office framing does become structural. The office will provide the shear strength to keep the loft from falling over.