That is what I thought too but I see tons of people with harnesses set up like that. I think it is different when they go back that far as appose to strait to the floor after the seat. I am not sure on the subject though.

 

RE: Belt height
It's not a matter of the overall height of the belts, it's the angle that the force is vectored through

If the shoulder belts are anchored straight to the floor behind the seat, the force of an impact will pull the straps against the back of the seat... basically tearing the back of the seat off, and going slack. Once the belts go slack, well it's like not having belts.

You ultimately want to have less than a 20 deg angle on the shoulder harness belts to the anchor point.

By having the anchor point farther to the rear, the angle decreases.
You'll see a lot of old race cars with seat belts anchored in the trunk



http://teinusa-blog.com/using-racing-harnesses/

 

i do something similar because my sparco seat doesnt give a lot of room on the latch. For clearence i would just flip it around and it snugs me in a lot more.