Well unless I'm mistaken, all the T-34 students are in the back seat for their instrument flights with the IP up front. And if I remember right, the wx mins are pretty high for their normal flights. And the T-45 starts the same way with the stud in the back for the instruments. We didn't sit up front for instrument flights until after our first instrument check.
You're in the back because you can't go under the hood in the front seat. Gotta be able to see and avoid traffic.