Its a frameset that comes with 2 different sets of dropouts, allowing you to run it geared, or fixed/ss
It is not meant to go anywhere near a track.
Poor design for the one on the left.
I think it's more convenient to have a fixed position for the rear wheel axle and the disc brake caliper on the dropout and a slot where it's attached to the frame. In that way, both the rear wheel and brake caliper are moved when adjusting the chain tension.
Now you have to re-adjust the brake caliper each time you change gears for example.
How it exactly works with replacing a wheel (moving front/aft) with the disc between the brake pads: I don't know. Didn't experience that with SS or FG or these fork ends. But I can think of some problems there.
Poor design for the one on the left.
I think it's more convenient to have a fixed position for the rear wheel axle and the disc brake caliper on the dropout and a slot where it's attached to the frame. In that way, both the rear wheel and brake caliper are moved when adjusting the chain tension.
Now you have to re-adjust the brake caliper each time you change gears for example.
How it exactly works with replacing a wheel (moving front/aft) with the disc between the brake pads: I don't know. Didn't experience that with SS or FG or these fork ends. But I can think of some problems there.