Right - but when contractor A lays the track and contractor B does the formwork and contractor C does the concrete pour, allowances have to be made when somebody screws up. I agree though, if I were doing it, I'd probably come up with a fixture or form that clips over the rail to guarantee the correct "cutout" in the concrete gets silohetted. But I'm looking at this as an automation designer not a construction/civil engineer. 
It could just be a cover that stays on until winter is done and then gets removed once the "guts" are installed. Seems pretty nice for a temporary cover though.
It could just be a cover that stays on until winter is done and then gets removed once the "guts" are installed. Seems pretty nice for a temporary cover though.