Hypothetically , if im in a little cessna 150 and the runway is 10,000 feet long , im tracking the runway ,THEN when i cannot land on it , im going to maintain RWY heading as per clearance !! Maybe if im taking off with a B747 on a 7000 RWY at gross weight, i wont be worried about tracking RWY after 500 feet height since I will be landing off the end of it anyways, therefore i will go from take-off to tracking RWY heading in a slow smooth movement as per ATC instruction? Is this reasonable ?